Following the release of Office Communications Server 2007 Sasa Juratovic posted a PowerShell script  to retrieve user IM conversations form the archiving database.  (http://communicationsserverteam.com/archive/2008/01/14/69.aspx)

With the release of Office Communications Server 2007 R2 there were changes in the archiving database schema allowing the text/html content type for storage of user instant messages.  This schema change caused the previous script to only report the first message in a conversation when reporting against an OCS R2 archiving database.  An updated script that will account for this additional content type that works for retrieving instant messages from both the OCS 2007 and OCS 2007 R2 archiving database schemas has been posted.

The updated script can be found at: http://communicationsserverteam.com/files/555/download.aspx

--Nick Smith

MCS Senior Consultant