diff --git a/system/database/DB_active_rec.php b/system/database/DB_active_rec.php
index 89766e3..7162e2a 100644
--- a/system/database/DB_active_rec.php
+++ b/system/database/DB_active_rec.php
@@ -872,11 +872,11 @@
 	 * @param	integer	the offset value
 	 * @return	object
 	 */
-	public function limit($value, $offset = '')
+	public function limit($value, $offset = NULL)
 	{
 		$this->ar_limit = (int) $value;
 
-		if ($offset != '')
+		if ( ! is_null($offset))
 		{
 			$this->ar_offset = (int) $offset;
 		}