International number masking - OL2007

[©®]

I have all my Contacts in Outlook Express and their numbers are in
international format:
+1-234-567-8901
+44-20-81234567

When I import them (either from OE or Palm Desktop), OL2007 drops the "+"
and wants all my numbers to be in NAmerican format like so:
1 (234) 567-8901
44 (20) 81234567

I *must* have the "+" symbol in front of all my numbers so was wondering if
there was a way to edit/tweak the number mask? I have many contacts from
many countries so not all my numbers are in the 10 digit NAmerican format.
Thanks very much.