My colleague Claus-Ole just pointed me to a new update on Office Communicator 2007.
This update fixes four problems and especially interesting is a fix for Terminal Server users and a enhancement to security in the High Security Policy mode, where the ABS, Custom Presence and Tabs URL's now require HTTPS. Following are the fixes -
951870 - Event IDs 8239 and 8206 are logged when you schedule and then cancel a meeting in Communicator 2007
949498 - Error message when a Communicator 2007 user sends a message that contains only Japanese characters to Communicator 2005 users: "<Username> cannot receive message in the format you used"
951871 - The presence status changes to Away for all Terminal Server users when an administrator locks the desktop or lets the screen saver run in Communicator 2007
951868 - Registry settings for certain protocols are overwritten, and Communicator 2007 becomes the default application for these protocols when you log on to Communicator 2007