8320 Desktop Manager Crashing

I have a client who continually needs to reset the calendar information on his BlackBerry. What happens is the Desktop Manager Program "Stops Responding" during the calendar sync. The way I fix it is by doing a one way sync from calendar to device, the setting the two way sync back up.

He runs Windows Vista and Desktop Manager version 4.5. The OS on his phone is version 4.5.x. He has a Microsoft Exchange account for his desktop calendar, and I think it is a certain type of calendar entry that creates the problem.

What I wonder is if upgrading to Desktop Manager 5.0 will solve this issue. And, if upgrading to BDM 5.0 is okay with the 8320.

Thanks for you help.