[rules-users] question about 'from'

When using the new 'from' feature, does Drools handle null values correctly? For example, let's say I have a rule like this: rule check when Integer() from helper.getId(); then ... end I tried returning null from getId(), but it caused Drools to throw an exception. So what I'm currently doing is have getId() return a collection, which may be empty. In this case Drools handles it without problem. Is there a better way to do this? I just don't want to wrap everything in a collection. thanks. sam