diff --git a/system/libraries/Session/drivers/Session_database_driver.php b/system/libraries/Session/drivers/Session_database_driver.php
index cb152f9..6a7282b 100644
--- a/system/libraries/Session/drivers/Session_database_driver.php
+++ b/system/libraries/Session/drivers/Session_database_driver.php
@@ -354,7 +354,7 @@
 	{
 		if ($this->_platform === 'mysql')
 		{
-			$arg = $session_id.($this->_config['match_ip'] ? '_'.$_SERVER['REMOTE_ADDR'] : '');
+			$arg = md5($session_id.($this->_config['match_ip'] ? '_'.$_SERVER['REMOTE_ADDR'] : ''));
 			if ($this->_db->query("SELECT GET_LOCK('".$arg."', 300) AS ci_session_lock")->row()->ci_session_lock)
 			{
 				$this->_lock = $arg;
@@ -417,4 +417,4 @@
 
 		return parent::_release_lock();
 	}
-}
\ No newline at end of file
+}