550c550,551
< count += self._ccObject.drain(drain_event)
---
> if not self._ccObject.drain(drain_event):
> count = 1
563c564
< if isinstance(self, System):
---
> if isinstance(self, SimObject) and not isinstance(self, ParamContext):
668c669,670
< raise AttributeError, "Can't resolve proxy '%s' from '%s'" % \
---
> raise AttributeError, \
> "Can't resolve proxy '%s' from '%s'" % \