Here is a notification utility smartWatchM for Sony Ericsoon BT watch (MBW-150). It supports all main features of Sony Ericsson phones and it even has some extra functions.

It’s developed for Smartphones/Windows Mobile Standard but works on all WM 5/6 devices (with MS BT stack).

Compatibility:

Sony Ericsson MBW-100 (usable, but complicated menu access or watch control – no issues)
Sony Ericsson MBW-150 (recommended – no issues)
Sony Ericsson MBW-200 (recommended – no issues but smaller resolution than MBW-1×0 – 80×16 instead of 96×16)
Abacus Caller ID Watch (or similar Fossil watch) (just notifications, no menu or control – no issues)
Citizen i:VIRT (W71 – not stable)
LM Technologies LM957/LM958/Fake MBW-150 (Bluetooth Watch Sports/Classic) (just notifications, no menu or control – no issues)
LM Technologies LM959 (Bluetooth Vibrating Bracelet) (complicated connection/reconnection)
LM Technologies Bracelet with LCD (currenly vibrate only, complicated connection/reconnection)
Sony Ericsson HBH-DS980 (setup, just a test)
Prada Link (LBA-T950 – not stable)

http://forum.xda-developers.com/showthread.php?t=362218