Using another user's contact list to send to multiple contacts

Hey all.

The help desk guys came to ask me this one, and I was stumped. A user wants to send email to multiple recipients on another users' contact list. They setup the permissions properly, so the contacts are visible, but there doesn't seem to be a way to make those addresses show up in the address book when sending an email. You can send email if you open their contact list, and right-click a contact and choose new message to contact, (and you can actually do this by control-clicking multiple contacts to send email to multiple recipients), but I'm looking for a way to have the addresses show up in outlook.

I can't add another outlook address book, nor can I make the remote contact list my primary contact folder. Anyone know of a way to make this work?

Thanks in advance
Max