Entourage on Exchange help

I help an office with their systems. They have Exchange 2003 running and the mac users have 10.5 on macBooks with Entourage 2008 and all the latest updates up to today (including system software). Out of the 5 or 6 people who are using 10.5, several consistently have database problems or sync problems and, of course, its impossible to find specific instructions to help them with their exact problem, aside from recreating the user profile and re-downloading all the data.

The issue I'd like help with is if someone knows about this: a user is in a plane for 10 hours and cleans up her deleted items and contacts - she is offline the whole time. She comes back, connects to the server and Entourage disregards all the edits she did and resyncs her email folders from the server, restoring the emails she deleted. Other times, she does the same, comes back, has no problems and a month or two later has a database issue that requires profile recreation or emptying cache of a folder. WHen it is restored, all the information she removed is back on the system. The computer otherwise has no problems syncing to the server and always connects - in and out of the office.

I hate entourage and wish we could use Outlook, but no go ... Let me know, thanks.