diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 256f9f5bdfe..d06ca63996d 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -1669,11 +1669,13 @@ static void do_inherit_parent_constructor(zend_class_entry *ce)
 	} else {
 		/* don't inherit the old style constructor if we already have the new style cconstructor */
 		if (!zend_hash_exists(&ce->function_table, ce->name, ce->name_length+1)) {
-			if (zend_hash_find(&ce->parent->function_table, ce->parent->name, ce->parent->name_length+1, (void **)&function)==SUCCESS) {
+			char *lcname = zend_str_tolower_dup(ce->parent->name, ce->parent->name_length);
+			if (zend_hash_find(&ce->parent->function_table, lcname, ce->parent->name_length+1, (void **)&function)==SUCCESS) {
 				/* inherit parent's constructor */
 				zend_hash_update(&ce->function_table, ce->name, ce->name_length+1, function, sizeof(zend_function), NULL);
 				function_add_ref(function);
 			}
+			efree(lcname);
 		}
 	}
 	ce->constructor = ce->parent->constructor;