[AccessD] Losing control event connections

Dear list,

I seem to recollect past discussions of something causing form controls
to lose the connection to code subroutines for their events; that is
there is a subroutine for a control event but it does not show in the
controls event properties and does not fire when the even occurs.  I
just ran into a form today that was working and now does not work.  When
I looked the event subroutines are there but the properties are not set.
There are three controls with this problem.  None of them have been
renamed.  This is an Access 97 database.

Has anyone else experienced this behavior?  Anyone know what causes it?

Doug