MCL crashing with divide by zero error

[seth@aic.hrl.hac.com]

I'm stymied. I have some code that works fine in one instance and
causes a divide by zero crash to the debugger in another. I thought
MCL is supposed to trap /0 and and be graceful. The error occurs when
adding a subview to a window. The window is not visible and the
addition occurs during the initialize-instance :after method. The
dialog item being added is a subclass of sequence-dialog-item. I
create three of them and the second two are added without problem. The
first one seems to be the culprit and only if the sequence has length
> 1. I'm at my wits end.

Ideas?

Seth