[AccessD] data not entered error not triggering

I have a wierd thing occurring.  I have a form where the user enters data.
If they don't select a combo (put a FK in a field) and try to close the form
by clicking the x in the upper right corner, an error is triggered.  If they
click my close button, the form closes but the JET data error never
triggers.

My close button just does a docmd.close.

has anyone ever seen this?

John W. Colby
www.colbyconsulting.com