Well not really.
Microsoft Lync is pretty much the only enterprise class telephony platform that does not directly support SIP endpoints. Microsoft insists that doing so will compromise its rich user experience it has worked so hard to craft. Instead, it sold rights to Polycom and Aastra to manufacture and distribute Microsoft proprietary phones. These phones were mostly designed by Microsoft, use many of the exact same components (as specified by Microsoft), and include Microsoft designed firmware. This solution works pretty well, and the phones do indeed offer several unique capabilities not found on most enterprise systems (such as access to your contacts).
But this limited selection of handsets creates a few voids in the Microsoft desktop family, namely wireless handsets.
Snom was the first and fastest to see an opportunity and devised a solution to make its SIP phones work nicely with OCS and Lync. Microsoft and Snom has slowly been releasing “Qualified” statements on specific models (the all pretty much work the same). Supposedly, the wireless DECT M9 works with Lync, but its not blessed yet.
Aastra is the first to bring a supported DECT wireless phone to the Lync solution, but its not through its MS licensing arrangement. Its Aastra’s SIP-DECT mobility wireless handsets.
How did they do it?
The solution involves two of Microsoft’s friends.