I would suggest that you use a third-party tool either to synchronize the data with an Exchange public folder or to add to the webservice to make it look to Outlook like a SharePoint list. See http://www.outlookcode.com/d/database.htm. Regarding the SharePoint-spoof approach, there are a couple of good articles from Microsoft bloggers, but I just can't lay my hands on them this mroning.

Signature
Sue Mosher, Outlook MVP
Author of Configuring Microsoft Outlook 2003
http://www.turtleflock.com/olconfig/index.htm
and Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> Hi,
> I have an external application holding information about all my
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> Any help/hint in what direction to go is much appreciated!
> Bjorn