Microsoft released a new update for OC 2007 and the update fixes the following issues -
949894 - Presence functions are disabled in Communicator 2007 when you use a time zone that includes a negative partial hour on a client computer
948733 - Error message when you try to shut down a client computer that is running Office Communicator 2007: "The data file 'Mailbox - user' was not closed properly"
950492 - You cannot manually change your status from "Away" in Communicator 2007 when you use a portable computer to connect to a remote computer
948159 - Error message in Communicator 2007 if the Outlook profile file name contains non-English characters: "There was a problem connecting to Microsoft Office Outlook"
948737 - A Communicator 2007 user hears a long dial tone mixed with the streaming audio if the user takes a USB telephony device handset off the hook and then uses the device to stream audio from another application
948120 - An audio conference or a video conference fails in Communicator 2007 when you try to invite a new participant to create a multiparty conference
Find the KB/download here.