Can cache empty collections

I should be able to cache an "empty" collection.

I have a some objects, where 90% of these have on-to-many relations with zero associated elements.
This causes doctrine to run a query each time, instead of cache it as empty relation.

lib/Doctrine/ORM/Cache/Persister/AbstractEntityPersister.php

@@ -543,7 +543,7 @@ abstract class AbstractEntityPersister implements CachedEntityPersister
 
         $list = $this->persister->loadOneToManyCollection($assoc, $sourceEntity, $coll);
 
-        if ($hasCache && ! empty($list)) {
+        if ($hasCache) {
             $persister->storeCollectionCache($key, $list);
 
             if ($this->cacheLogger) {