There is a post on this board under the subject "I am going to jump out the window from this" by user "Pocket Mac Anne", which helped me a great deal. I was able to synch both calander, contacts and address book without any issues. I have pasted her post below....hopefully this will help you.
"Wow, I'm really sorry you are having so much trouble.
If you are using an 8100 with PocketMac, you should try the latest version 4.0.20 that RIM posted recently, here: http://www.discoverblackberry.com/di..._solutions.jsp
Whether you are using PocketMac or any other sync solution, there is something you need to know about Entourage... its indices have a tendency to get old and out of date, and you definitely should run your Database Maintenance procedures frequently to keep it in shape.
Sync programs must tie into Entourage's exporting program to get the data out. Entourage does NOT allow us to have access to all the fields, especially custom fields. We literally have to work with whatever it spits out. I have seen it spit out garbled data (names not matching addresses, phones, email) when it looks just fine on the screen. Spooky.
The good news is that if you quit Entourage, then hold down your Option key while you restart it, you can run the Rebuild Database utility and Entourage will straighten itself out.
As a bonus, it backs up the database at the same time. So, we often recommend this as a basic maintenance procedure.
Incidentally, the way I discovered this was testing with my own very extensive Entourage database. The records looked fine on the screen but were all mixed up on a device I was using. In desperation, I did the rebuild and synced again. The records on the device were magically corrected.
I then took my backed up "messy" data, and duplicated it on another Mac and device so I could prove it was the database and not a bug in PocketMac or something wrong with my (at the time) G4 PowerPC iMac.
The moral of the story: whichever sync solution you choose, make sure you back up and rebuild Entourage databases because they need a little more care than some other types.
Have a great day!"