Another TOA Question

Really, TOA seems to be about the least documented feature in Word!

Ok, still using Word 2003. Is there a way to change the way a TOA is
sorted? Right now it sorts in "Word order" rather than "numerical" or "XP
style". So, for example, the cite "City Code 10-2" appears before the cite
"City Code 6-1".

I tried changing the long-cite for the one that should be higher-up by
inserting a "0" before the 6 and marking it "hidden" under Font/Format. It
fixed the sort order, but the TOA ignores the hidden property and displays
the 0 in the TOA.

Any ideas or clever tricks (other than putting them into separate categories
-- I realize I could do that, but it would be very very messy to do as there
are several instances, and it would require many categories).

Thanks