When I took delivery of my new 2008 Edge Limited, I was very disappointed that SYNC was incompatable with my Verizon Treo 700w phone. It wouldn't load the address book, etc.
When I got home, I did some searching on the web and found JetWare http://www.jetwaremobile.com/
It seems the problem is with the various devices Bluetooth Hands-Free Profile that don't allow them to "talk" to SYNC.
I downloaded their small software install (you get a free trial), loaded it on my phone and, when I went back out to the car, it linked immediately with full capability and does so every time I get in the car. The only problem I have now is that, at random while driving, SYNC will dispaly a message that the phone has disconnected. When I look at the phone, it is fine. I have to re-attach the phone in SYNC and then it will work for a few more days.