diff --git a/Zend/zend_API.c b/Zend/zend_API.c
index c22cef47088..0be5dba2764 100644
--- a/Zend/zend_API.c
+++ b/Zend/zend_API.c
@@ -1145,6 +1145,7 @@ int zend_register_functions(zend_class_entry *scope, zend_function_entry *functi
 	char *lowercase_name;
 	int fname_len;
 
+	memset(internal_function, 0, sizeof(zend_function));
 	if (type==MODULE_PERSISTENT) {
 		error_type = E_CORE_WARNING;
 	} else {