After I have tested the February update for Lync 2013 server, I have noticed that the server has to boot twice to get all the changes.
For one of my customers we noticed that Edge and FrontEnd server had some issues and after the second reboot well then it started to work again.
One of the Error that we had was that mobile users and external users had issues to sign into Lync form external. Also that SNOM m9R had some signin issue aswell With the Error named "Final handshake".
But the second boot from the frontend server solved this issue.