diff --git a/lua.c b/lua.c
index 7429b8b..b05f4ef 100755
--- a/lua.c
+++ b/lua.c
@@ -424,7 +424,7 @@ try_again:
 					add_next_index_zval(callbacks, val);
 				} else {
 					zval *v;
-					ulong longkey;
+					zend_ulong longkey;
 					zend_string *key;
 					zval zkey;