Issues that this update package fixes
This cumulative update fixes the following issues:-
981218 (http://support.microsoft.com/kb/981218/ ) A call is dropped when a media time-out occurs on the gateway side of the Office Communications Server 2007 R2, Mediation Server
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981250 (http://support.microsoft.com/kb/981250/ ) The Office Communications Server 2007 R2, Mediation Server does not send a response to the PSTN gateway when the Mediation Server cannot contact the front-end server
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972772 (http://support.microsoft.com/kb/972772/ ) Video is not displayed after you enable Quality of Service (QoS) at the pool level in Communications Server 2007 R2 and you enable QoS on a client computer
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972770 (http://support.microsoft.com/kb/972770/ ) An update package enables Office Communications Server 2007 R2, Mediation Server to include a diversion header in the re-invite after the server processes a 302 redirection
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968954 (http://support.microsoft.com/kb/968954/ ) Communications Server 2007 R2 front-end server does not recognize a 504 error message that is sent by Communications Server 2007 R2 Mediation Server after you install update 956829
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