I have a control ("Location Reference") that has three
possible formats. (Numeric, Alpha-numeric, Text Only)  
Everything works fine when I create a "new" location but
if I want to edit an existing one and change the format,
the new inputmask command does not overwrite the existing
one.

Note: when editing, the existing value (say 'Text Only')
is read and the applicable inputmask is re-assigned.  If
the user deletes all characters then a new inputmask is
specified based in the first keypress event.  This new
inputmask designation does not seem to overwrite the old
one even though the code is processed...  What am I doing
wrong?