type casting via the # symbol hangs drools

when trying to assign type casted value to variable in when clausule Drools hangs without any message on rule load. It even hangs my Eclipse environment in build process.

this will hang:
$q:Message(id=="item", answered==true, $v:value#DataItemPrice)

this will not hang:
$q:Message(id=="item", answered==true, value instanceof DataItemPrice, $v:value)

Maybe it is not supported to type cast the property into variable in this way, but it should not hang the Drools engine.

I will try to add full example.