Don't bother. By the time you've imported them, they'll have moved to other servers. Instead, concentrate on managing your "safe senders" and "safe recipients" lists -- the people whose addresses you want to make sure get through the built-in filter.
--
Sue Mosher, Outlook MVP
Author of Configuring Microsoft Outlook 2003
and Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers