diff --git a/templates/settings.php b/templates/settings.php
--- a/templates/settings.php
+++ b/templates/settings.php
@@ -1,46 +1,46 @@
 <form id="sql" action="#" method="post">
     <fieldset class="personalblock">
         <legend><?php echo $l->t('SQL'); ?></legend>
             <p><label for="sql_type"><?php echo $l->t('SQL Driver');?></label>
                 <?php $db_driver = array('mysql' => 'MySQL', 'pgsql' => 'PostgreSQL');?>
                 <select id="sql_type" name="sql_type">
                     <?php 
                         foreach ($db_driver as $driver => $name):
                             echo $_['sql_type'];
                             if($_['sql_type'] == $driver): ?>
                                 <option selected="selected" value="<?php echo $driver; ?>"><?php echo $name; ?></option>
                             <?php else: ?>
                                 <option value="<?php echo $driver; ?>"><?php echo $name; ?></option>
                             <?php endif;
                         endforeach; ?>
                 </select>
             </p>
 
             <p><label for="sql_host"><?php echo $l->t('Host');?></label><input type="text" id="sql_host" name="sql_host" value="<?php echo $_['sql_host']; ?>"></p>
             <p><label for="sql_user"><?php echo $l->t('Username');?></label><input type="text" id="sql_user" name="sql_user" value="<?php echo $_['sql_user']; ?>" /></p>
             <p><label for="sql_database"><?php echo $l->t('Database');?></label><input type="text" id="sql_database" name="sql_database" value="<?php echo $_['sql_database']; ?>" /></p>
             <p><label for="sql_password"><?php echo $l->t('Password');?></label><input type="password" id="sql_password" name="sql_password" value="<?php echo $_['sql_password']; ?>" /></p>
             <p><label for="sql_table"><?php echo $l->t('Table');?></label><input type="text" id="sql_table" name="sql_table" value="<?php echo $_['sql_table']; ?>" /></p>
             <p><label for="sql_column_username"><?php echo $l->t('Username Column');?></label><input type="text" id="sql_column_username" name="sql_column_username" value="<?php echo $_['sql_column_username']; ?>" /></p>
             <p><label for="sql_column_password"><?php echo $l->t('Password Column');?></label><input type="text" id="sql_column_password" name="sql_column_password" value="<?php echo $_['sql_column_password']; ?>" /></p>
             <p><label for="crypt_type"><?php echo $l->t('Encryption Type');?></label>
-                <?php $crypt_types = array('md5' => 'MD5', 'md5crypt' => 'MD5 Crypt', 'cleartext' => 'Cleartext', 'mysql_encrypt' => 'mySQL ENCRYPT()', 'system' => 'System (crypt)', 'mysql_password' => 'mySQL PASSWORD()');?>
+                <?php $crypt_types = array('md5' => 'MD5', 'md5crypt' => 'MD5 Crypt', 'cleartext' => 'Cleartext', 'mysql_encrypt' => 'mySQL ENCRYPT()', 'system' => 'System (crypt)', 'mysql_password' => 'mySQL PASSWORD()', 'joomla' => 'Joomla MD5 Encryption');?>
                 <select id="crypt_type" name="crypt_type">
                     <?php 
                         foreach ($crypt_types as $driver => $name):
                             echo $_['crypt_type'];
                             if($_['crypt_type'] == $driver): ?>
                                 <option selected="selected" value="<?php echo $driver; ?>"><?php echo $name; ?></option>
                             <?php else: ?>
                                 <option value="<?php echo $driver; ?>"><?php echo $name; ?></option>
                             <?php endif;
                         endforeach; ?>
                 </select>
             </p>            
             <p><label for="sql_column_active"><?php echo $l->t('User Active Column');?></label><input type="text" id="sql_column_active" name="sql_column_active" value="<?php echo $_['sql_column_active']; ?>" /></p>
             <p><label for="strip_domain"><?php echo $l->t('Strip Domain Part from Username');?></label><input type="checkbox" id="strip_domain" name="strip_domain" value="1"<?php if($_['strip_domain']) echo ' checked'; ?> title="Strip Domain Part from Username when logging in and retrieving username lists"></p>
             <p><label for="default_domain"><?php echo $l->t('Add default domain to Usernames');?></label><input type="text" id="default_domain" name="default_domain" value="<?php echo $_['default_domain']; ?>" /></p>
         <input type="hidden" name="requesttoken" value="<?php echo $_['requesttoken'] ?>" id="requesttoken" />
         <input type="submit" value="<?php echo $l->t('Save'); ?>" />
     </fieldset>
 </form>
diff --git a/user_sql.php b/user_sql.php
--- a/user_sql.php
+++ b/user_sql.php
@@ -1,521 +1,544 @@
 <?php
 
 /**
  * ownCloud - user_sql
  *
- * @author Andreas Böhler
+ * @author Andreas Böhler and contributors
  * @copyright 2012/2013 Andreas Böhler <andreas (at) aboehler (dot) at>
  *
+ * credits go to Ed W for several SQL injection fixes and caching support
+ * credits go to Frédéric France for providing Joomla support
+ * credits go to 
+ *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
  * License as published by the Free Software Foundation; either
  * version 3 of the License, or any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
  *
  * You should have received a copy of the GNU Affero General Public
  * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
 
 class OC_USER_SQL extends OC_User_Backend implements OC_User_Interface {
 
     // cached settings
     protected $sql_host;
     protected $sql_username;
     protected $sql_database;
     protected $sql_password;
     protected $sql_table;
     protected $sql_column_username;
     protected $sql_column_password;
     protected $sql_column_active;
     protected $sql_type;
     protected $db_conn;
     protected $db;
     protected $default_domain;
     protected $strip_domain;
     protected $crypt_type;
 
     public function __construct() 
     {
         $this->db_conn = false;
         $this->sql_host = OCP\Config::getAppValue('user_sql', 'sql_host', '');
         $this->sql_username = OCP\Config::getAppValue('user_sql', 'sql_user', '');
         $this->sql_database = OCP\Config::getAppValue('user_sql', 'sql_database', '');
         $this->sql_password = OCP\Config::getAppValue('user_sql', 'sql_password', '');
         $this->sql_table = OCP\Config::getAppValue('user_sql', 'sql_table', '');
         $this->sql_column_username = OCP\Config::getAppValue('user_sql', 'sql_column_username', '');
         $this->sql_column_password = OCP\Config::getAppValue('user_sql', 'sql_column_password', '');
         $this->sql_column_active = OCP\Config::getAppValue('user_sql', 'sql_column_active', '');
         $this->sql_type = OCP\Config::getAppValue('user_sql', 'sql_type', '');
         $this->default_domain = OCP\Config::getAppValue('user_sql', 'default_domain', '');
         $this->strip_domain = OCP\Config::getAppValue('user_sql', 'strip_domain', 0);
         $this->crypt_type = OCP\Config::getAppValue('user_sql', 'crypt_type', 'md5crypt');
         $dsn = $this->sql_type.":host=".$this->sql_host.";dbname=".$this->sql_database;
         try 
         {
             $this->db = new PDO($dsn, $this->sql_username, $this->sql_password);
             $this->db_conn = true;
         }
         catch (PDOException $e) 
         {
             OC_Log::write('OC_USER_SQL', 'Failed to connect to the database: ' . $e->getMessage(), OC_Log::ERROR);
         }
         return false;
     }
 
     public function implementsAction($actions) 
     {
         return (bool)((OC_USER_BACKEND_CHECK_PASSWORD) & $actions);
     }
 
     public function createUser() {
         // Can't create user
         OC_Log::write('OC_USER_SQL', 'Not possible to create local users from web frontend using SQL user backend', OC_Log::ERROR);
         return false;
     }
 
     public function deleteUser( $uid ) 
     {
         // Can't delete user
         OC_Log::write('OC_USER_SQL', 'Not possible to delete local users from web frontend using SQL user backend', OC_Log::ERROR);
         return false;
     }
 
     public function setPassword ( $uid, $password ) {
         // Update the user's password - this might affect other services, that user the same database, as well
         OC_Log::write('OC_USER_SQL', "Entering setPassword for UID: $uid", OC_Log::DEBUG);
         if(!$this->db_conn)
         {
             return false;
         }
         $uid = trim($uid);
         if($this->default_domain && (strpos($uid, '@') === false))
         {
             $uid .= "@".$this->default_domain;
         }
         $query = "SELECT $this->sql_column_password FROM $this->sql_table WHERE $this->sql_column_username = :uid";
         OC_Log::write('OC_USER_SQL', "Preparing query: $query", OC_Log::DEBUG);
         $result = $this->db->prepare($query);
         $result->bindParam(":uid", $uid);
         OC_Log::write('OC_USER_SQL', "Executing query...", OC_Log::DEBUG);
         if(!$result->execute())
         {
             return false;
         }
         OC_Log::write('OC_USER_SQL', "Fetching result...", OC_Log::DEBUG);
         $row = $result->fetch();
         if(!$row)
         {
             return false;
         }
         $old_password = $row[$this->sql_column_password];
         $enc_password = $this->pacrypt($password, $old_password);
         $query = "UPDATE $this->sql_table SET $this->sql_column_password = :enc_password WHERE $this->sql_column_username = :uid";
         OC_Log::write('OC_USER_SQL', "Preapring query: $query", OC_Log::DEBUG);
         $result = $this->db->prepare($query);
         $result->bindParam(":enc_password", $enc_password);
         $result->bindParam(":uid", $uid);
         OC_Log::write('OC_USER_SQL', "Executing query...", OC_Log::DEBUG);
         if(!$result->execute())
         {
             $err = $result->errorInfo();
             OC_Log::write('OC_USER_SQL', "Query failed: ".$err[2], OC_Log::DEBUG);
             OC_Log::write('OC_USER_SQL', "Could not update password!", OC_Log::ERROR);
             return false;
         }
         OC_Log::write('OC_USER_SQL', "Updated password successfully, return true", OC_Log::DEBUG);
         return true;
     }
 
     /**
     * @brief Check if the password is correct
     * @param $uid The username
     * @param $password The password
     * @returns true/false
     *
     * Check if the password is correct without logging in the user
     */
     public function checkPassword($uid, $password)
     {
         OC_Log::write('OC_USER_SQL', "Entering checkPassword() for UID: $uid", OC_Log::DEBUG);
         if(!$this->db_conn)
         {
             return false;
         }
         $uid = trim($uid);
         if($this->default_domain && (strpos($uid, '@') === false))
         {
             $uid .= "@".$this->default_domain;
         }
         $uid = strtolower($uid);
         
         $query = "SELECT $this->sql_column_username, $this->sql_column_password FROM $this->sql_table WHERE $this->sql_column_username = :uid";
         if($this->sql_column_active != '')
             $query .= " AND $this->sql_column_active = 1";
         OC_Log::write('OC_USER_SQL', "Preparing query: $query", OC_Log::DEBUG);
         $result = $this->db->prepare($query);
         $result->bindParam(":uid", $uid);
         OC_Log::write('OC_USER_SQL', "Executing query...", OC_Log::DEBUG);
         if(!$result->execute())
         {
             $err = $result->errorInfo();
             OC_Log::write('OC_USER_SQL', "Query failed: ".$err[2], OC_Log::DEBUG);
             return false;
         }
         OC_Log::write('OC_USER_SQL', "Fetching row...", OC_Log::DEBUG);
         $row = $result->fetch();
         if(!$row)
         {
             OC_Log::write('OC_USER_SQL', "Got no row, return false", OC_Log::DEBUG);
             return false;
         }
         OC_Log::write('OC_USER_SQL', "Encrypting and checking password", OC_Log::DEBUG);
         if($this->pacrypt($password, $row[$this->sql_column_password]) == $row[$this->sql_column_password])
         {
             OC_Log::write('OC_USER_SQL', "Passwords matching, return true", OC_Log::DEBUG);
             if($this->strip_domain)
             {
                 $uid = explode("@", $uid);
                 $uid = $uid[0];
             }
             return $uid;
         }
         else
         {
             OC_Log::write('OC_USER_SQL', "Passwords do not match, return false", OC_Log::DEBUG);
             return false;
         }
     }
 
     /**
     * @brief Get a list of all users
     * @returns array with all uids
     *
     * Get a list of all users.
     */
 
     public function getUsers($search = '', $limit = null, $offset = null)
     {
-       OC_Log::write('OC_USER_SQL', "Entering getUsers() with Search: $search", OC_Log::DEBUG);
+       OC_Log::write('OC_USER_SQL', "Entering getUsers() with Search: $search, Limit: $limit, Offset: $offset", OC_Log::DEBUG);
        $users = array();
        if(!$this->db_conn)
        {
         return false;
        }
        $query = "SELECT $this->sql_column_username FROM $this->sql_table";
        if($search != '')
           $query .= " WHERE $this->sql_column_username LIKE :search";
         if($this->sql_column_active != '')
         {
             if($search != '')
                 $query .= " AND";
             else
                 $query .= " WHERE";
             $query .= " $this->sql_column_active = 1";
         }
+       $query .= " ORDER BY $this->sql_column_username";
        if($limit != null)
        {
           $limit = intval($limit);
           $query .= " LIMIT $limit";
        }
        if($offset != null)
        {
           $offset = intval($offset);
           $query .= " OFFSET $offset";
        }
        OC_Log::write('OC_USER_SQL', "Preparing query: $query", OC_Log::DEBUG);
        $result = $this->db->prepare($query);
        if($search != '')
        {
           $search = "%$search%";
           $result->bindParam(":search", $search);
        }
        OC_Log::write('OC_USER_SQL', "Executing query...", OC_Log::DEBUG);
        if(!$result->execute())
        {
         $err = $result->errorInfo();
         OC_Log::write('OC_USER_SQL', "Query failed: ".$err[2], OC_Log::DEBUG);
         return array();
        }
        OC_Log::write('OC_USER_SQL', "Fetching results...", OC_Log::DEBUG);
        while($row = $result->fetch())
        {
            $uid = $row[$this->sql_column_username];
            if($this->strip_domain)
            {
                $uid = explode("@", $uid);
                $uid = $uid[0];
            }
            $users[] = strtolower($uid);
        }
        OC_Log::write('OC_USER_SQL', "Return list of results", OC_Log::DEBUG);
        return $users;
     }
 
     /**
     * @brief check if a user exists
     * @param string $uid the username
     * @return boolean
     */
 
     public function userExists($uid)
     {
+    	static $cached_exists;
         OC_Log::write('OC_USER_SQL', "Entering userExists() for UID: $uid", OC_Log::DEBUG);
         if(!$this->db_conn)
         {
             return false;
         }
         $uid = trim($uid);
         if($this->default_domain && (strpos($uid, '@') === false))
         {
             $uid .= "@".$this->default_domain;
         }
         $uid = strtolower($uid);
         
+        if ($uid === $cached_exists) {
+            OC_Log::write('OC_USER_SQL', "User exists (using cache), return true", OC_Log::DEBUG);
+            return true;
+        }
         $query = "SELECT $this->sql_column_username FROM $this->sql_table WHERE $this->sql_column_username = :uid";
         if($this->sql_column_active != '')
             $query .= " AND $this->sql_column_active = 1";
         OC_Log::write('OC_USER_SQL', "Preparing query: $query", OC_Log::DEBUG);
         $result = $this->db->prepare($query);
         $result->bindParam(":uid", $uid);
         OC_Log::write('OC_USER_SQL', "Executing query...", OC_Log::DEBUG);
         if(!$result->execute())
         {
             $err = $result->errorInfo();
             OC_Log::write('OC_USER_SQL', "Query failed: ".$err[2], OC_Log::DEBUG);
             return false;
         }
         OC_Log::write('OC_USER_SQL', "Fetching results...", OC_Log::DEBUG);
         $row = $result->fetch();
         if(!$row)
         {
             OC_Log::write('OC_USER_SQL', "Empty row, user does not exists, return false", OC_Log::DEBUG);
             return false;
         }
         else
         {
             OC_Log::write('OC_USER_SQL', "User exists, return true", OC_Log::DEBUG);
+            $cached_exists = $uid;
             return true;
         }
 
     }
        
      /**
      * The following functions were directly taken from PostfixAdmin and just slightly modified
      * to suit our needs.
      * Encrypt a password, using the apparopriate hashing mechanism as defined in 
      * config.inc.php ($this->crypt_type). 
      * When wanting to compare one pw to another, it's necessary to provide the salt used - hence
      * the second parameter ($pw_db), which is the existing hash from the DB.
      *
      * @param string $pw
      * @param string $encrypted password
      * @return string encrypted password.
      */
     private function pacrypt ($pw, $pw_db="")
     {
         OC_Log::write('OC_USER_SQL', "Entering private pacrypt()", OC_Log::DEBUG);
         $pw = stripslashes($pw);
         $password = "";
         $salt = "";
 
         if ($this->crypt_type == 'md5crypt') {
             $split_salt = preg_split ('/\$/', $pw_db);
             if (isset ($split_salt[2])) {
                 $salt = $split_salt[2];
             }
             $password = $this->md5crypt ($pw, $salt);
         }
 
         elseif ($this->crypt_type == 'md5') {
             $password = md5($pw);
         }
 
         elseif ($this->crypt_type == 'system') { // We never generate salts, as user creation is not allowed here
             $password = crypt ($pw, $pw_db);
         }
 
         elseif ($this->crypt_type == 'cleartext') {
             $password = $pw;
         }
 
         // See https://sourceforge.net/tracker/?func=detail&atid=937966&aid=1793352&group_id=191583
         // this is apparently useful for pam_mysql etc.
         elseif ($this->crypt_type == 'mysql_encrypt')
         {
             if(!$this->db_conn)
             {
                 return false;
             }        
             if ($pw_db!="") {
                 $salt=substr($pw_db,0,2);
                 $query = "SELECT ENCRYPT(:pw, :salt);";
             } else {
                 $query = "SELECT ENCRYPT(:pw);";
             }
 
             $result = $this->db->prepare($query);
             $result->bindParam(":pw", $pw);
             if($pw_db != "")
                 $result->bindParam(":salt", $salt);
             if(!$result->execute())
             {
                 return false;
             }
             $row = $result->fetch();
             if(!$row)
             {
                 return false;
             }
             $password = $row[0];
         }
 
         elseif($this->crypt_type == 'mysql_password')
         {
             if(!$this->db_conn)
             {
                 return false;
             }        
             $query = "SELECT PASSWORD(:pw);";
 
             $result = $this->db->prepare($query);
             $result->bindParam(":pw", $pw);
             if(!$result->execute())
             {
                 return false;
             }
             $row = $result->fetch();
             if(!$row)
             {
                 return false;
             }
             $password = $row[0];
         }
+        
+        // The following is by Frédéric France
+        elseif($this->crypt_type == 'joomla') 
+        {
+            $split_salt = preg_split ('/:/', $pw_db);
+            if(isset($split_salt[1])) 
+            {
+                $salt = $split_salt[1];
+            }
+            $password = ($salt) ? md5($pw.$salt) : md5($pw);
+            $password.= ':'.$salt;
+        }
 
         else {
             OC_Log::write('OC_USER_SQL', "unknown/invalid crypt_type settings: $this->crypt_type", OC_Log::ERROR);
             die ('unknown/invalid Encryption type setting: ' . $this->crypt_type);
         }
         OC_Log::write('OC_USER_SQL', "pacrypt() done, return", OC_Log::DEBUG);
         return $password;
     }
 
     //
     // md5crypt
     // Action: Creates MD5 encrypted password
     // Call: md5crypt (string cleartextpassword)
     //
 
     private function md5crypt ($pw, $salt="", $magic="")
     {
         $MAGIC = "$1$";
 
         if ($magic == "") $magic = $MAGIC;
         if ($salt == "") $salt = $this->create_salt ();
         $slist = explode ("$", $salt);
         if ($slist[0] == "1") $salt = $slist[1];
 
         $salt = substr ($salt, 0, 8);
         $ctx = $pw . $magic . $salt;
         $final = $this->pahex2bin (md5 ($pw . $salt . $pw));
 
         for ($i=strlen ($pw); $i>0; $i-=16)
         {
             if ($i > 16)
             {
                 $ctx .= substr ($final,0,16);
             }
             else
             {
                 $ctx .= substr ($final,0,$i);
             }
         }
         $i = strlen ($pw);
 
         while ($i > 0)
         {
             if ($i & 1) $ctx .= chr (0);
             else $ctx .= $pw[0];
             $i = $i >> 1;
         }
         $final = $this->pahex2bin (md5 ($ctx));
 
         for ($i=0;$i<1000;$i++)
         {
             $ctx1 = "";
             if ($i & 1)
             {
                 $ctx1 .= $pw;
             }
             else
             {
                 $ctx1 .= substr ($final,0,16);
             }
             if ($i % 3) $ctx1 .= $salt;
             if ($i % 7) $ctx1 .= $pw;
             if ($i & 1)
             {
                 $ctx1 .= substr ($final,0,16);
             }
             else
             {
                 $ctx1 .= $pw;
             }
             $final = $this->pahex2bin (md5 ($ctx1));
         }
         $passwd = "";
         $passwd .= $this->to64 (((ord ($final[0]) << 16) | (ord ($final[6]) << 8) | (ord ($final[12]))), 4);
         $passwd .= $this->to64 (((ord ($final[1]) << 16) | (ord ($final[7]) << 8) | (ord ($final[13]))), 4);
         $passwd .= $this->to64 (((ord ($final[2]) << 16) | (ord ($final[8]) << 8) | (ord ($final[14]))), 4);
         $passwd .= $this->to64 (((ord ($final[3]) << 16) | (ord ($final[9]) << 8) | (ord ($final[15]))), 4);
         $passwd .= $this->to64 (((ord ($final[4]) << 16) | (ord ($final[10]) << 8) | (ord ($final[5]))), 4);
         $passwd .= $this->to64 (ord ($final[11]), 2);
         return "$magic$salt\$$passwd";
     }
 
     private function create_salt ()
     {
         srand ((double) microtime ()*1000000);
         $salt = substr (md5 (rand (0,9999999)), 0, 8);
         return $salt;
     }
     
     private function pahex2bin ($str)
     {
         if(function_exists('hex2bin'))
         {
             return hex2bin($str);
         }
         else
         {
             $len = strlen ($str);
             $nstr = "";
             for ($i=0;$i<$len;$i+=2)
             {
                 $num = sscanf (substr ($str,$i,2), "%x");
                 $nstr.=chr ($num[0]);
             }
             return $nstr;
         }
     }
 
     private function to64 ($v, $n)
     {
         $ITOA64 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
         $ret = "";
         while (($n - 1) >= 0)
         {
             $n--;
             $ret .= $ITOA64[$v & 0x3f];
             $v = $v >> 6;
         }
         return $ret;
     }
 
 }
 
 ?>