A new update for Lync 2010 for Windows Phone has been released shipped with Oct 2012 CU. Please see blow for detail information.
Note: After you install this update on the phone, you would find that the version number in the app (from the about screen) incorrectly states version 4.1.8092.0. The actual version number is 4.3.8092.1 as stated in the Windows Phone Marketplace.
For the whole updates released in Oct 2012 CU, please refer to the following link:
For the Update version information for each CU, please refer to the follow link: