Update: Actually it is much simpler than I thought. Pair the phones and power down the phone, restart. ISync sends you a text message with a tiny agent that installs on your Nokia 6620 phone, and you are good to go. Same with s710a. Good luck guys
Just installed Tiger, and one of the things I was most looking forward to was new improved iSync 2.0. Apple officially says it works with a whole slew of phones, including Nokia 6620 and Sony s710a. I have both, tried to sync but failed. I am not the only one who is having these problems. The iSync thread has many complaining about issues of some sort with many of the new phones. I guess, I will have to wait for the updates.