Detect Mail Status in mbox - not mail spool

[Anita Lewis <ajlewis2@intac.com>]

I'm using icewm.  There is a nifty little icon that shows the mail status on
the toolbar.  The problem is that I have procmail deliver all my mail to
folders - much of it to separate folders, and what's left goes in mbox.  The
reason for this is that I have various versions of Debian installed and want
to get to my mail (in separate /home) in whichever one I am currently using. 
I don't want a joint /var for them in order to keep the apt caches separate.

How do I set up to have the mail status checked in somewhere other than
/var/spool/mail?

Thanks,
Anita