diff --git a/system/database/drivers/cubrid/cubrid_driver.php b/system/database/drivers/cubrid/cubrid_driver.php
index 48b9042..c89a924 100644
--- a/system/database/drivers/cubrid/cubrid_driver.php
+++ b/system/database/drivers/cubrid/cubrid_driver.php
@@ -179,9 +179,18 @@
 	 */
 	public function version()
 	{
-		return isset($this->data_cache['version'])
-			? $this->data_cache['version']
-			: $this->data_cache['version'] = cubrid_get_server_info($this->conn_id);
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
+
+		return ( ! $this->conn_id OR ($version = cubrid_get_server_info($this->conn_id)) === FALSE)
+			? FALSE
+			: $this->data_cache['version'] = $version;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mysql/mysql_driver.php b/system/database/drivers/mysql/mysql_driver.php
index 2457e55..b1edc29 100644
--- a/system/database/drivers/mysql/mysql_driver.php
+++ b/system/database/drivers/mysql/mysql_driver.php
@@ -191,9 +191,21 @@
 	 */
 	public function version()
 	{
-		return isset($this->data_cache['version'])
-			? $this->data_cache['version']
-			: $this->data_cache['version'] = @mysql_get_server_info($this->conn_id);
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
+
+		if ( ! $this->conn_id OR ($version = @mysql_get_server_info($this->conn_id)) === FALSE)
+		{
+			return FALSE;
+		}
+
+		return $this->data_cache['version'] = $version;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/mysqli/mysqli_driver.php b/system/database/drivers/mysqli/mysqli_driver.php
index 7d2507b..ae17703 100644
--- a/system/database/drivers/mysqli/mysqli_driver.php
+++ b/system/database/drivers/mysqli/mysqli_driver.php
@@ -173,9 +173,16 @@
 	 */
 	public function version()
 	{
-		return isset($this->data_cache['version'])
-			? $this->data_cache['version']
-			: $this->data_cache['version'] = $this->conn_id->server_info;
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
+
+		return $this->data_cache['version'] = $this->conn_id->server_info;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/oci8/oci8_driver.php b/system/database/drivers/oci8/oci8_driver.php
index 38d2395..b2663e2 100644
--- a/system/database/drivers/oci8/oci8_driver.php
+++ b/system/database/drivers/oci8/oci8_driver.php
@@ -240,9 +240,21 @@
 	 */
 	public function version()
 	{
-		return isset($this->data_cache['version'])
-			? $this->data_cache['version']
-			: $this->data_cache['version'] = oci_server_version($this->conn_id);
+		if (isset($this->data_cache['version']))
+		{
+			return $this->data_cache['version'];
+		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
+
+		if ( ! $this->conn_id OR ($version = oci_server_version($this->conn_id)) === FALSE)
+		{
+			return FALSE;
+		}
+
+		return $this->data_cache['version'] = $version;
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index 57a3c5c..923f0e1 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -165,6 +165,10 @@
 		{
 			return $this->data_cache['version'];
 		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
 
 		// Not all subdrivers support the getAttribute() method
 		try
diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 028dc19..40f21b1 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -204,8 +204,12 @@
 		{
 			return $this->data_cache['version'];
 		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
 
-		if (($pg_version = pg_version($this->conn_id)) === FALSE)
+		if ( ! $this->conn_id OR ($pg_version = pg_version($this->conn_id)) === FALSE)
 		{
 			return FALSE;
 		}
diff --git a/system/database/drivers/sqlsrv/sqlsrv_driver.php b/system/database/drivers/sqlsrv/sqlsrv_driver.php
index de3d873..d3999bf 100644
--- a/system/database/drivers/sqlsrv/sqlsrv_driver.php
+++ b/system/database/drivers/sqlsrv/sqlsrv_driver.php
@@ -275,8 +275,12 @@
 		{
 			return $this->data_cache['version'];
 		}
+		elseif ( ! $this->conn_id)
+		{
+			$this->initialize();
+		}
 
-		if (($info = sqlsrv_server_info($this->conn_id)) === FALSE)
+		if ( ! $this->conn_id OR ($info = sqlsrv_server_info($this->conn_id)) === FALSE)
 		{
 			return FALSE;
 		}