I read another forum and found out how it can be done. It's a bit cumbersome, but not too bad. You need to changed your preferences for the Apple Address Book app to make the vCards version 2.1 (I think it defaults to v3.0).

You then need to manually exprort the addresses (one-by-one) to your desktop (or wherever on your HD).

You can use the built in OS X app called "Bluetooth File Exchange" to to a batch xfer of these exported vCard files to your phone. It worked for me.

The a640's Bluetooth profiles are:

1. HSP (headset profile)
2. HFP (hands free profile) (car kit)
3. DUN (dial up networking (use as modem -- 1xRTT, not EVDO)
4. OPP (object push profile) (send name card to another BT phone and it places it alphabetically in the address book)

I just got the Samsung A640 and it has bluetooth capabilities. My computer (Apple iMac) also has a bluetooth card in it. The computer can recognize that my phone is nearby but for some reason my phone doesnt want to sync with my computer. Does anyone know if it is possible to sync this phone with my computer? I am mainly looking to maintain my contacts list.
Thanks for the help.