diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index c3eb7cc..521bdfd 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -57,6 +57,8 @@
 	protected $_count_string = 'SELECT COUNT(*) AS ';
 	protected $_random_keyword;
 
+	protected $trans_enabled = FALSE;
+
 	// need to track the PDO options
 	public $options = array();
 
@@ -80,6 +82,10 @@
 		{
 			$this->subdriver = 'dblib';
 		}
+		elseif ($this->subdriver === '4D')
+		{
+			$this->subdriver = '4d';
+		}
 
 		// clause and character used for LIKE escape sequences
 		// this one depends on the driver being used
@@ -88,9 +94,6 @@
 			$this->_escape_char = '';
 			$this->_like_escape_str = " {escape '%s'} ";
 		}
-
-		$this->trans_enabled = FALSE;
-//		$this->_random_keyword = ' RND('.time().')'; // database specific random keyword
 	}
 
 	/**
@@ -142,23 +145,13 @@
 		}
 
 		// Add the database name to the DSN, if needed
-		if (stripos($this->dsn, 'dbname') === FALSE && $this->subdriver === '4D')
-		{
-			$this->dsn .= 'dbname='.$this->database.';';
-		}
-		elseif (stripos($this->dsn, 'database') === FALSE && $this->subdriver === 'ibm')
+		if (stripos($this->dsn, 'database') === FALSE && $this->subdriver === 'ibm')
 		{
 			if (stripos($this->dsn, 'dsn') === FALSE)
 			{
 				$this->dsn .= 'database='.$this->database.';';
 			}
 		}
-
-		// Add charset to the DSN, if needed
-		if ( ! empty($this->char_set) && $this->subdriver === '4D')
-		{
-			$this->dsn .= 'charset='.$this->char_set.';';
-		}
 	}
 
 	// --------------------------------------------------------------------
@@ -489,24 +482,6 @@
 	// --------------------------------------------------------------------
 
 	/**
-	 * Truncate statement
-	 *
-	 * Generates a platform-specific truncate string from the supplied data
-	 *
-	 * If the database does not support the truncate() command,
-	 * then this method maps to 'DELETE FROM table'
-	 *
-	 * @param	string	the table name
-	 * @return	string
-	 */
-	protected function _truncate($table)
-	{
-		return 'DELETE FROM '.$table;
-	}
-
-	// --------------------------------------------------------------------
-
-	/**
 	 * Limit string
 	 *
 	 * Generates a platform-specific LIMIT clause
diff --git a/system/database/drivers/pdo/subdrivers/pdo_4d_driver.php b/system/database/drivers/pdo/subdrivers/pdo_4d_driver.php
new file mode 100644
index 0000000..a680a84
--- /dev/null
+++ b/system/database/drivers/pdo/subdrivers/pdo_4d_driver.php
@@ -0,0 +1,239 @@
+<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP 5.2.4 or newer
+ *
+ * NOTICE OF LICENSE
+ *
+ * Licensed under the Open Software License version 3.0
+ *
+ * This source file is subject to the Open Software License (OSL 3.0) that is
+ * bundled with this package in the files license.txt / license.rst.  It is
+ * also available through the world wide web at this URL:
+ * http://opensource.org/licenses/OSL-3.0
+ * If you did not receive a copy of the license and are unable to obtain it
+ * through the world wide web, please send an email to
+ * licensing@ellislab.com so we can send you a copy immediately.
+ *
+ * @package		CodeIgniter
+ * @author		EllisLab Dev Team
+ * @copyright	Copyright (c) 2008 - 2012, EllisLab, Inc. (http://ellislab.com/)
+ * @license		http://opensource.org/licenses/OSL-3.0 Open Software License (OSL 3.0)
+ * @link		http://codeigniter.com
+ * @since		Version 3.0.0
+ * @filesource
+ */
+
+/**
+ * PDO 4D Database Adapter Class
+ *
+ * Note: _DB is an extender class that the app controller
+ * creates dynamically based on whether the query builder
+ * class is being used or not.
+ *
+ * @package		CodeIgniter
+ * @subpackage	Drivers
+ * @category	Database
+ * @author		EllisLab Dev Team
+ * @link		http://codeigniter.com/user_guide/database/
+ */
+class CI_DB_pdo_4d_driver extends CI_DB_pdo_driver {
+
+	public $subdriver = '4d';
+
+	// The character used for escaping
+	protected $_escape_char = array('[', ']');
+
+	protected $_random_keyword = ' RAND()';
+
+	/**
+	 * Constructor
+	 *
+	 * Builds the DSN if not already set.
+	 *
+	 * @param	array
+	 * @return	void
+	 */
+	public function __construct($params)
+	{
+		parent::__construct($params);
+
+		if (empty($this->dsn))
+		{
+			$this->dsn = '4D:host='.(empty($this->hostname) ? 'localhost' : $this->hostname);
+
+			empty($this->port) OR $this->dsn .= ';port='.$this->port;
+			empty($this->database) OR $this->dsn .= ';dbname='.$this->database;
+			empty($this->char_set) OR $this->dsn .= ';charset='.$this->char_set;
+		}
+		elseif ( ! empty($this->char_set) && strpos($this->dsn, 'charset=', 3) === FALSE)
+		{
+			$this->dsn .= ';charset='.$this->char_set;
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show table query
+	 *
+	 * Generates a platform-specific query string so that the table names can be fetched
+	 *
+	 * @param	bool
+	 * @return	string
+	 */
+	protected function _list_tables($prefix_limit = FALSE)
+	{
+		return 'SELECT '.$this->escape_identifiers('TABLE_NAME').' FROM '.$this->escape_identifiers('_USER_TABLES');
+
+		if ($prefix_limit === TRUE && $this->dbprefix !== '')
+		{
+			$sql .= ' WHERE '.$this->escape_identifiers('TABLE_NAME')." LIKE '".$this->escape_like_str($this->dbprefix)."%' "
+				.sprintf($this->_like_escape_str, $this->_like_escape_chr);
+		}
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Show column query
+	 *
+	 * Generates a platform-specific query string so that the column names can be fetched
+	 *
+	 * @param	string	the table name
+	 * @return	string
+	 */
+	protected function _list_columns($table = '')
+	{
+		return 'SELECT '.$this->escape_identifiers('COLUMN_NAME').' FROM '.$this->escape_identifiers('_USER_COLUMNS')
+			.' WHERE '.$this->escape_identifiers('TABLE_NAME').' = '.$this->escape($table);
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Field data query
+	 *
+	 * Generates a platform-specific query so that the column data can be retrieved
+	 *
+	 * @param	string	the table name
+	 * @return	string
+	 */
+	protected function _field_data($table)
+	{
+		return 'SELECT * FROM '.$this->protect_identifiers($table, TRUE, NULL, FALSE).' LIMIT 1';
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * From Tables
+	 *
+	 * This function implicitly groups FROM tables so there is no confusion
+	 * about operator precedence in harmony with SQL standards
+	 *
+	 * @param	array
+	 * @return	string
+	 */
+	protected function _from_tables($tables)
+	{
+		return is_array($tables) ? implode(', ', $tables) : $tables;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Update statement
+	 *
+	 * Generates a platform-specific update string from the supplied data
+	 *
+	 * @param	string	the table name
+	 * @param	array	the update data
+	 * @param	array	the where clause
+	 * @param	array	the orderby clause (ignored)
+	 * @param	array	the limit clause (ignored)
+	 * @param	array	the like clause
+	 * @return	string
+         */
+	protected function _update($table, $values, $where, $orderby = array(), $limit = FALSE, $like = array())
+	{
+		foreach ($values as $key => $val)
+		{
+			$valstr[] = $key.' = '.$val;
+		}
+
+		$where = empty($where) ? '' : ' WHERE '.implode(' ', $where);
+
+		if ( ! empty($like))
+		{
+			$where .= ($where === '' ? ' WHERE ' : ' AND ').implode(' ', $like);
+		}
+
+		return 'UPDATE '.$table.' SET '.implode(', ', $valstr).$where;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Truncate statement
+	 *
+	 * Generates a platform-specific truncate string from the supplied data
+	 *
+	 * If the database does not support the truncate() command,
+	 * then this method maps to 'DELETE FROM table'
+	 *
+	 * @param	string	the table name
+	 * @return	string
+	 */
+	protected function _truncate($table)
+	{
+		return 'TRUNCATE TABLE '.$table;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Delete statement
+	 *
+	 * Generates a platform-specific delete string from the supplied data
+	 *
+	 * @param	string	the table name
+	 * @param	array	the where clause
+	 * @param	array	the like clause
+	 * @param	string	the limit clause (ignored)
+	 * @return	string
+	 */
+	protected function _delete($table, $where = array(), $like = array(), $limit = FALSE)
+	{
+		$conditions = array();
+
+		empty($where) OR $conditions[] = implode(' ', $where);
+		empty($like) OR $conditions[] = implode(' ', $like);
+
+		$conditions = (count($conditions) > 0) ? ' WHERE '.implode(' AND ', $conditions) : '';
+
+		return 'DELETE FROM '.$table.$conditions;
+	}
+
+	// --------------------------------------------------------------------
+
+	/**
+	 * Limit string
+	 *
+	 * Generates a platform-specific LIMIT clause
+	 *
+	 * @param	string	the sql query string
+	 * @param	int	the number of rows to limit the query to
+	 * @param	int	the offset value
+	 * @return	string
+	 */
+	protected function _limit($sql, $limit, $offset)
+	{
+		return $sql.' LIMIT '.$limit.($offset ? ' OFFSET '.$offset : '');
+	}
+
+}
+
+/* End of file pdo_4d_driver.php */
+/* Location: ./system/database/drivers/pdo/subdrivers/pdo_4d_driver.php */
\ No newline at end of file
diff --git a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
index 0429207..3a2679f 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_dblib_driver.php
@@ -223,7 +223,7 @@
 		empty($where) OR $conditions[] = implode(' ', $where);
 		empty($like) OR $conditions[] = implode(' ', $like);
 
-		$conditions = (count($conditions) > 0) ? ' WHERE '.implde(' AND ', $conditions) : '';
+		$conditions = (count($conditions) > 0) ? ' WHERE '.implode(' AND ', $conditions) : '';
 
 		return ($limit)
 			? 'WITH ci_delete AS (SELECT TOP '.$limit.' * FROM '.$table.$conditions.') DELETE FROM ci_delete'
diff --git a/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php b/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
index 7abdc59..59ae853 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_pgsql_driver.php
@@ -265,7 +265,7 @@
 	 */
 	protected function _limit($sql, $limit, $offset)
 	{
-		return $sql.' LIMIT '.$limit.($offset == 0 ? '' : ' OFFSET '.$offset);
+		return $sql.' LIMIT '.$limit.($offset ? '' : ' OFFSET '.$offset);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
index f7e2420..5afd749 100644
--- a/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
+++ b/system/database/drivers/pdo/subdrivers/pdo_sqlsrv_driver.php
@@ -278,7 +278,7 @@
 		empty($where) OR $conditions[] = implode(' ', $where);
 		empty($like) OR $conditions[] = implode(' ', $like);
 
-		$conditions = (count($conditions) > 0) ? ' WHERE '.implde(' AND ', $conditions) : '';
+		$conditions = (count($conditions) > 0) ? ' WHERE '.implode(' AND ', $conditions) : '';
 
 		return ($limit)
 			? 'WITH ci_delete AS (SELECT TOP '.$limit.' * FROM '.$table.$conditions.') DELETE FROM ci_delete'