Microsoft has updated the Windows based Communicator Mobile software to support the Next version of Windows Mobile and a couple of other fixes:
Homescreen support for new homescreens in Windows Mobile 6.5+ phones.
Integration within the phone dialer for Windows Mobile 6.5+ phones.
Communicator Mobile 2007 R2 now recognizes when the phone is roaming, and by default does not sign in to roaming networks.
Additional support for joining conference calls from a Windows Mobile appointment. To do this, press Menu, and then press Join Conference.
Enables users to log on with a username of the format firstname.lastname@example.org, in addition to domainuser.
When placing Call via Work calls, callbacks are now automatically accepted.
Microsoft Installer (MSI) installation on Windows XP Service Pack 3 (SP3) fails. In this situation, users should install Communicator Mobile 2007 R2 by using a .Cab installation.
AT&T FUZE devices set for High-Speed Downlink Packet Access (HSDPA) connection cannot handle voice and data at the same time. This causes Call via Work calls to fail unless the device is reverted to 3rd Generation (3G) by disabling HSDPA.
Get the updated software here: