I spent the entire weekend installing/uninstalling pocketmac and syncing it a millions different ways. I was getting errors, multiple instances of events, and contacts that just did not want to sync. Solution: Installed BB Desktop v4.6 on a PC.
Go into backup/restore and make a backup of your BB.
Then go to advanced. This screen will show you what is on your BB. Just clear the calendar and contacts (be sure you have a backup-just in case)
Plug it into your Mac and sync your calendar and contacts-it worked fine for me. Unfortunately, if you do not have access to a PC....
I think my existing data on my blackberry was screwing things up, plus I think my database was corrupt from all of the failed syncs I was doing. It worked for me-hope it works for others too!