Need help figuring out how to migrate the activities that belong to contacts and accounts in vTiger to SugarCRM CE.

I'm migrating from vTiger 5.2.1 to SugarCRM 6.3.1. Using the export/import features I've gotten the accounts, contacts, Leads and opts migrated over, but can't seem to figure out how to get the activities associated with them over as well. Also, not as important, but I'd like to migrate the calendar over, and don't see a way to do that.

Anyone run into this before, ot have any suggestions? I searched the forums, but didn't see any posts that had a solution.

TIA

Shawn