EC subclass constructor trouble

I have an EC class that extends EOEditingContext. Occasionally, when 
creating a child EC of an existing EC, I get a NPE on the last line of 
the constructor (see below). Any idea how that is possible? I'm at a loss.

init() is not a likely culprit; all it does is a single call to 
super.setMessageHandler().

zak.


public I3pkbEditingContext(Session s, EOEditingContext ec)
{
     super(ec);
     init();
     User u = s.user();
     if (u != null)
         this.user = (User) EOUtilities.localInstanceOfObject(this, u);
}