IQEvent.as - line 41
var event:IQEvent = new IQEvent();
var event:IQEvent = new IQEvent(this.type);
The IQEvent Contstructor takes a single parameter for type, which is not being passed in the clone() method added 7/15/09.
ModelChangedEvent - line 42
event.firstItem = _fieldItem;
event.firstItem = _firstItem;
_fieldItem is undefined. I assume it should be _firstItem, which is already defined.