I was looking into this about 8 months ago when I first got my pearl. There was a little progress, but IIRC most success was had via syncing Linux with something like google/yahoo/etc and then syncing the berry OTA. There was some software that would allow Linux to see a BB connected via USB, which would sort of see an old 7100g that I was borrowing at the time. It was also able to charge the 7100g and theoretically a pearl as well, but I couldn't ever get it to see the pearl.
Try this link to get started:
Synchronizing a BlackBerry in Linux » cb.blog
I haven't followed this much, as I am syncing via Google OTA and that is working reasonably well. I dual boot with XP so I hop on there once in a while to make a backup with DM.
Edit: I'm running Ubuntu Hardy Heron