diff --git a/dibi/drivers/mssql.php b/dibi/drivers/mssql.php
index c500526..3aa9e19 100644
--- a/dibi/drivers/mssql.php
+++ b/dibi/drivers/mssql.php
@@ -29,6 +29,7 @@
  *   - 'persistent' - try to find a persistent link?
  *   - 'database' - the database name to select
  *   - 'lazy' - if TRUE, connection will be established only when required
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -67,7 +68,9 @@ class DibiMsSqlDriver extends DibiObject implements IDibiDriver
 		DibiConnection::alias($config, 'password', 'pass');
 		DibiConnection::alias($config, 'host', 'hostname');
 
-		if (empty($config['persistent'])) {
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
+		} elseif (empty($config['persistent'])) {
 			$this->connection = @mssql_connect($config['host'], $config['username'], $config['password'], TRUE); // intentionally @
 		} else {
 			$this->connection = @mssql_pconnect($config['host'], $config['username'], $config['password']); // intentionally @
diff --git a/dibi/drivers/mssql2005.php b/dibi/drivers/mssql2005.php
index 12af80c..7ee422d 100644
--- a/dibi/drivers/mssql2005.php
+++ b/dibi/drivers/mssql2005.php
@@ -27,6 +27,7 @@
  *   - 'options' - connection info array {@link http://msdn.microsoft.com/en-us/library/cc296161(SQL.90).aspx}
  *   - 'lazy' - if TRUE, connection will be established only when required
  *   - 'charset' - character encoding to set (default is UTF-8)
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -66,7 +67,9 @@ class DibiMsSql2005Driver extends DibiObject implements IDibiDriver
 	{
 		DibiConnection::alias($config, 'host', 'hostname');
 
-		if (isset($config['options'])) {
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
+		} elseif (isset($config['options'])) {
 			$this->connection = sqlsrv_connect($config['host'], $config['options']);
 		} else {
 			$this->connection = sqlsrv_connect($config['host']);
diff --git a/dibi/drivers/mysql.php b/dibi/drivers/mysql.php
index 3b8be27..7d02f65 100644
--- a/dibi/drivers/mysql.php
+++ b/dibi/drivers/mysql.php
@@ -35,6 +35,7 @@
  *   - 'options' - driver specific constants (MYSQL_*)
  *   - 'sqlmode' - see http://dev.mysql.com/doc/refman/5.0/en/server-sql-mode.html
  *   - 'lazy' - if TRUE, connection will be established only when required
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -77,30 +78,35 @@ class DibiMySqlDriver extends DibiObject implements IDibiDriver
 		DibiConnection::alias($config, 'host', 'hostname');
 		DibiConnection::alias($config, 'options');
 
-		// default values
-		if (!isset($config['username'])) $config['username'] = ini_get('mysql.default_user');
-		if (!isset($config['password'])) $config['password'] = ini_get('mysql.default_password');
-		if (!isset($config['host'])) {
-			$host = ini_get('mysql.default_host');
-			if ($host) {
-				$config['host'] = $host;
-				$config['port'] = ini_get('mysql.default_port');
-			} else {
-				if (!isset($config['socket'])) $config['socket'] = ini_get('mysql.default_socket');
-				$config['host'] = NULL;
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
+
+		} else {
+			// default values
+			if (!isset($config['username'])) $config['username'] = ini_get('mysql.default_user');
+			if (!isset($config['password'])) $config['password'] = ini_get('mysql.default_password');
+			if (!isset($config['host'])) {
+				$host = ini_get('mysql.default_host');
+				if ($host) {
+					$config['host'] = $host;
+					$config['port'] = ini_get('mysql.default_port');
+				} else {
+					if (!isset($config['socket'])) $config['socket'] = ini_get('mysql.default_socket');
+					$config['host'] = NULL;
+				}
 			}
-		}
 
-		if (empty($config['socket'])) {
-			$host = $config['host'] . (empty($config['port']) ? '' : ':' . $config['port']);
-		} else {
-			$host = ':' . $config['socket'];
-		}
+			if (empty($config['socket'])) {
+				$host = $config['host'] . (empty($config['port']) ? '' : ':' . $config['port']);
+			} else {
+				$host = ':' . $config['socket'];
+			}
 
-		if (empty($config['persistent'])) {
-			$this->connection = @mysql_connect($host, $config['username'], $config['password'], TRUE, $config['options']); // intentionally @
-		} else {
-			$this->connection = @mysql_pconnect($host, $config['username'], $config['password'], $config['options']); // intentionally @
+			if (empty($config['persistent'])) {
+				$this->connection = @mysql_connect($host, $config['username'], $config['password'], TRUE, $config['options']); // intentionally @
+			} else {
+				$this->connection = @mysql_pconnect($host, $config['username'], $config['password'], $config['options']); // intentionally @
+			}
 		}
 
 		if (!is_resource($this->connection)) {
diff --git a/dibi/drivers/mysqli.php b/dibi/drivers/mysqli.php
index 2c4fa92..9ddad7b 100644
--- a/dibi/drivers/mysqli.php
+++ b/dibi/drivers/mysqli.php
@@ -35,6 +35,7 @@
  *   - 'options' - driver specific constants (MYSQLI_*)
  *   - 'sqlmode' - see http://dev.mysql.com/doc/refman/5.0/en/server-sql-mode.html
  *   - 'lazy' - if TRUE, connection will be established only when required
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -78,27 +79,32 @@ class DibiMySqliDriver extends DibiObject implements IDibiDriver
 		DibiConnection::alias($config, 'options');
 		DibiConnection::alias($config, 'database');
 
-		// default values
-		if (!isset($config['username'])) $config['username'] = ini_get('mysqli.default_user');
-		if (!isset($config['password'])) $config['password'] = ini_get('mysqli.default_pw');
-		if (!isset($config['socket'])) $config['socket'] = ini_get('mysqli.default_socket');
-		if (!isset($config['port'])) $config['port'] = NULL;
-		if (!isset($config['host'])) {
-			$host = ini_get('mysqli.default_host');
-			if ($host) {
-				$config['host'] = $host;
-				$config['port'] = ini_get('mysqli.default_port');
-			} else {
-				$config['host'] = NULL;
-				$config['port'] = NULL;
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
+
+		} else {
+			// default values
+			if (!isset($config['username'])) $config['username'] = ini_get('mysqli.default_user');
+			if (!isset($config['password'])) $config['password'] = ini_get('mysqli.default_pw');
+			if (!isset($config['socket'])) $config['socket'] = ini_get('mysqli.default_socket');
+			if (!isset($config['port'])) $config['port'] = NULL;
+			if (!isset($config['host'])) {
+				$host = ini_get('mysqli.default_host');
+				if ($host) {
+					$config['host'] = $host;
+					$config['port'] = ini_get('mysqli.default_port');
+				} else {
+					$config['host'] = NULL;
+					$config['port'] = NULL;
+				}
 			}
-		}
 
-		$this->connection = mysqli_init();
-		@mysqli_real_connect($this->connection, $config['host'], $config['username'], $config['password'], $config['database'], $config['port'], $config['socket'], $config['options']); // intentionally @
+			$this->connection = mysqli_init();
+			@mysqli_real_connect($this->connection, $config['host'], $config['username'], $config['password'], $config['database'], $config['port'], $config['socket'], $config['options']); // intentionally @
 
-		if ($errno = mysqli_connect_errno()) {
-			throw new DibiDriverException(mysqli_connect_error(), $errno);
+			if ($errno = mysqli_connect_errno()) {
+				throw new DibiDriverException(mysqli_connect_error(), $errno);
+			}
 		}
 
 		if (isset($config['charset'])) {
diff --git a/dibi/drivers/odbc.php b/dibi/drivers/odbc.php
index 9477312..9341dcf 100644
--- a/dibi/drivers/odbc.php
+++ b/dibi/drivers/odbc.php
@@ -28,6 +28,7 @@
  *   - 'password' (or 'pass')
  *   - 'persistent' - try to find a persistent link?
  *   - 'lazy' - if TRUE, connection will be established only when required
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -68,15 +69,19 @@ class DibiOdbcDriver extends DibiObject implements IDibiDriver
 		DibiConnection::alias($config, 'username', 'user');
 		DibiConnection::alias($config, 'password', 'pass');
 
-		// default values
-		if (!isset($config['username'])) $config['username'] = ini_get('odbc.default_user');
-		if (!isset($config['password'])) $config['password'] = ini_get('odbc.default_pw');
-		if (!isset($config['dsn'])) $config['dsn'] = ini_get('odbc.default_db');
-
-		if (empty($config['persistent'])) {
-			$this->connection = @odbc_connect($config['dsn'], $config['username'], $config['password']); // intentionally @
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
 		} else {
-			$this->connection = @odbc_pconnect($config['dsn'], $config['username'], $config['password']); // intentionally @
+			// default values
+			if (!isset($config['username'])) $config['username'] = ini_get('odbc.default_user');
+			if (!isset($config['password'])) $config['password'] = ini_get('odbc.default_pw');
+			if (!isset($config['dsn'])) $config['dsn'] = ini_get('odbc.default_db');
+
+			if (empty($config['persistent'])) {
+				$this->connection = @odbc_connect($config['dsn'], $config['username'], $config['password']); // intentionally @
+			} else {
+				$this->connection = @odbc_pconnect($config['dsn'], $config['username'], $config['password']); // intentionally @
+			}
 		}
 
 		if (!is_resource($this->connection)) {
diff --git a/dibi/drivers/oracle.php b/dibi/drivers/oracle.php
index 78b7565..1a18dd0 100644
--- a/dibi/drivers/oracle.php
+++ b/dibi/drivers/oracle.php
@@ -28,6 +28,7 @@
  *   - 'password' (or 'pass')
  *   - 'charset' - character encoding to set
  *   - 'lazy' - if TRUE, connection will be established only when required
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -70,7 +71,11 @@ class DibiOracleDriver extends DibiObject implements IDibiDriver
 		DibiConnection::alias($config, 'database', 'db');
 		DibiConnection::alias($config, 'charset');
 
-		$this->connection = @oci_new_connect($config['username'], $config['password'], $config['database'], $config['charset']); // intentionally @
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
+		} else {
+			$this->connection = @oci_new_connect($config['username'], $config['password'], $config['database'], $config['charset']); // intentionally @
+		}
 
 		if (!$this->connection) {
 			$err = oci_error();
diff --git a/dibi/drivers/pdo.php b/dibi/drivers/pdo.php
index 4af4ce2..7f6a51d 100644
--- a/dibi/drivers/pdo.php
+++ b/dibi/drivers/pdo.php
@@ -27,7 +27,7 @@
  *   - 'username' (or 'user')
  *   - 'password' (or 'pass')
  *   - 'options' - driver specific options array
- *   - 'pdo' - PDO object (optional)
+ *   - 'resource' - PDO object (optional)
  *   - 'lazy' - if TRUE, connection will be established only when required
  *
  * @author     David Grudl
@@ -69,11 +69,11 @@ class DibiPdoDriver extends DibiObject implements IDibiDriver
 		DibiConnection::alias($config, 'username', 'user');
 		DibiConnection::alias($config, 'password', 'pass');
 		DibiConnection::alias($config, 'dsn');
-		DibiConnection::alias($config, 'pdo');
+		DibiConnection::alias($config, 'resource', 'pdo');
 		DibiConnection::alias($config, 'options');
 
-		if ($config['pdo'] instanceof PDO) {
-			$this->connection = $config['pdo'];
+		if ($config['resource'] instanceof PDO) {
+			$this->connection = $config['resource'];
 
 		} else try {
 			$this->connection = new PDO($config['dsn'], $config['username'], $config['password'], $config['options']);
diff --git a/dibi/drivers/postgre.php b/dibi/drivers/postgre.php
index 5d23cbf..3ef1630 100644
--- a/dibi/drivers/postgre.php
+++ b/dibi/drivers/postgre.php
@@ -29,6 +29,7 @@
  *   - 'charset' - character encoding to set
  *   - 'schema' - the schema search path
  *   - 'lazy' - if TRUE, connection will be established only when required
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -66,23 +67,28 @@ class DibiPostgreDriver extends DibiObject implements IDibiDriver
 	 */
 	public function connect(array &$config)
 	{
-		if (isset($config['string'])) {
-			$string = $config['string'];
-		} else {
-			$string = '';
-			foreach (array('host','hostaddr','port','dbname','user','password','connect_timeout','options','sslmode','service') as $key) {
-				if (isset($config[$key])) $string .= $key . '=' . $config[$key] . ' ';
-			}
-		}
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
 
-		DibiDriverException::tryError();
-		if (empty($config['persistent'])) {
-			$this->connection = pg_connect($string, PGSQL_CONNECT_FORCE_NEW);
 		} else {
-			$this->connection = pg_pconnect($string, PGSQL_CONNECT_FORCE_NEW);
-		}
-		if (DibiDriverException::catchError($msg)) {
-			throw new DibiDriverException($msg, 0);
+			if (isset($config['string'])) {
+				$string = $config['string'];
+			} else {
+				$string = '';
+				foreach (array('host','hostaddr','port','dbname','user','password','connect_timeout','options','sslmode','service') as $key) {
+					if (isset($config[$key])) $string .= $key . '=' . $config[$key] . ' ';
+				}
+			}
+
+			DibiDriverException::tryError();
+			if (empty($config['persistent'])) {
+				$this->connection = pg_connect($string, PGSQL_CONNECT_FORCE_NEW);
+			} else {
+				$this->connection = pg_pconnect($string, PGSQL_CONNECT_FORCE_NEW);
+			}
+			if (DibiDriverException::catchError($msg)) {
+				throw new DibiDriverException($msg, 0);
+			}
 		}
 
 		if (!is_resource($this->connection)) {
diff --git a/dibi/drivers/sqlite.php b/dibi/drivers/sqlite.php
index 9fcc833..9da4be3 100644
--- a/dibi/drivers/sqlite.php
+++ b/dibi/drivers/sqlite.php
@@ -31,6 +31,7 @@
  *   - 'formatDateTime' - how to format datetime in SQL (@see date)
  *   - 'dbcharset' - database character encoding (will be converted to 'charset')
  *   - 'charset' - character encoding to set (default is UTF-8)
+ *   - 'resource' - connection resource (optional)
  *
  * @author     David Grudl
  * @copyright  Copyright (c) 2005, 2009 David Grudl
@@ -79,7 +80,9 @@ class DibiSqliteDriver extends DibiObject implements IDibiDriver
 		$this->fmtDateTime = isset($config['formatDateTime']) ? $config['formatDateTime'] : 'U';
 
 		$errorMsg = '';
-		if (empty($config['persistent'])) {
+		if (isset($config['resource'])) {
+			$this->connection = $config['resource'];
+		} elseif (empty($config['persistent'])) {
 			$this->connection = @sqlite_open($config['database'], 0666, $errorMsg); // intentionally @
 		} else {
 			$this->connection = @sqlite_popen($config['database'], 0666, $errorMsg); // intentionally @
diff --git a/dibi/libs/DibiFluent.php b/dibi/libs/DibiFluent.php
index fd6c2c8..d5fa606 100644
--- a/dibi/libs/DibiFluent.php
+++ b/dibi/libs/DibiFluent.php
@@ -119,7 +119,7 @@ class DibiFluent extends DibiObject
 			if ($arg === TRUE) { // flag
 				$args = array();
 
-			} elseif (is_string($arg) && preg_match('#^[a-z][a-z0-9_.]*$#i', $arg)) { // identifier
+			} elseif (is_string($arg) && preg_match('#^[a-z:_][a-z0-9_.:]*$#i', $arg)) { // identifier
 				$args = array('%n', $arg);
 
 			} elseif ($arg instanceof self) {