POP3 with Exchange 5.5 Configuration

Background – We have a Windows 2000 Network except our Exchange server which is still NT / Exchange 5.5. We have a few contractors and we want them to have access to out Exchange 5.5 server for messaging and calendar functions but we do not want them to log into the domain and we do not want them to have access to other file servers. I added Outlook 2003 and set them up with the POP3 option and this seems to work fine.

Question – How can I give them access to the Global Address Book that we maintain? I am still unable to figure that out.