diff --git a/system/database/drivers/interbase/interbase_driver.php b/system/database/drivers/interbase/interbase_driver.php
index fcefa6d..4044c45 100644
--- a/system/database/drivers/interbase/interbase_driver.php
+++ b/system/database/drivers/interbase/interbase_driver.php
@@ -309,7 +309,12 @@
 	 */
 	public function insert_id($generator_name, $inc_by=0)
 	{
-		return ibase_gen_id('"'.$generator_name.'"', $inc_by);
+		//If a generator hasn't been used before it will return 0
+		if($id = ibase_gen_id('"'.$generator_name.'"', $inc_by) !== 0)
+		{
+			return $id;
+		}
+		return ibase_gen_id('"'.$generator_name.'"', 1);
 	}
 
 	// --------------------------------------------------------------------