I highly recommend updating the ROM to 2.17.
You can backup your contacts and calendar entries with pocket pim backup for free.
http://www.freewareppc.com/database/pimbackup.shtml
I use this instead of activesync to backup.
After you update your rom, then let's see if you still have these errors. No point in spending a ton of time fixing a problem if you're going to hard reset anyways.
