What is the Mac story on OCS?

This was a question from a Northeastern school district:   Mac Messenger 7.0 Mac Messenger 7.0 is available for a Mac user to login into either Windows Live (MSN) or OCS 2007:                    Login to either Windows Live or OCS 2007   Messenger 7.0 client is similar to OC client on PC with presence, groups,…

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