On handheld, goto Options.. Applications.. Click trackwheel and select modules.
What is the version number on the net_rim* modules?
Open desktop manager, click on Help menu then About Desktop manager...
Goto handheld component tab,
what version of software is listed here?
if these versions dont match that could be one thing to look at fixing.
you could try a clean uninstall of all desktop/handheld software from your system and reinstall.