After a long wait the latest service pack for BlackBerry Enterprise Server now adds support for the IM Client for Lync and OCS R2. As many will know up until this release the only way to use the IM Client on your Blackberry was to retain a legacy OCS 2007 RTM Communicator Web Access (CWA) server running.
The release noted for BES for Exchange SP3 is available here as a PDF.
BES for Exchange SP3 can be obtained from here.
I’ve not had a chance to look how well this works, so if you try it please comment with your thoughts.