I believe I have the correct version of Windows Mobile installed on my phone. However, when I try to sign in I get the error message "You must update your version of Communicator Mobile before you can sign in. Contact your system administrator for the correct version."
Any ideas? Version is 2.0.387.0. I downloaded it from here:
http://www.microsoft.com/downloads/details.aspx?FamilyId=2EEA3E24-F216-4887-92B0-F37D942E26E0&displaylang=en