[rules-users] Nested classes in the fact model in Guvnor

If I have nested classes in my Java model, I find that the Guvnor is giving me the option to import classes using a "$" as the separator between the containing class name and the nested classname. However, validation of rules always fails saying that the class name with the "$" in it cannot be resolved. If I change these into "." then the problem goes away. Is this a known problem or am I missing something? I am using Drools 5.1.1 Chris Selwyn