After hours of trying different things I have finally found an inexpensive way to get my bluetooth phone to work with my Voice II intercom (btw this should work for any intercom with a phone in jack). The Motorola HF800 speakerphone is the solution. I have owned this for over six months but didn't know it had a 2.5mm out until just recently. I think there is a newer model but I don't know if it has the 2.5mm out. When not being used on you bike it works pretty well in the car. Here is a link: http://www.infosyncworld.com/news/n/4481.html
I have used this with my SMT5600 on my bike up to 70mph and have also tried it with a razr. This should work with any bluetooth phone.
They are selling new on Ebay for $25: http://cgi.ebay.com/New-Motorola-OEM...QQcmdZViewItem
All you need to do is plug a 2.5mm stereo cord from the HF800 to the phone in on the VoiceII. You will hear the phone ring in the helmet and the sound quality is awesome. I tested it talking to my wife up to 70mph. She said she couldn't tell I was on a motorcycle. I am not sure it matters when using it as a wireless headset jack but I would make sure the volume is all the way up on the HF800
This is a great solution for all Cingular users (and I assume T-mobile as well) as cingular phones pump a lot of interference through anything with a speaker. If I put my phone in the oddments box I hear interference while the phone is working. If I set it next to my computers speakers at the office I get a loud buzzing through the speakers. Now I can keep it in my pocket or velcroe it to a mount.
Let me share some of things that didn't work for me.
The BlueEar bluetooth headset (http://www.cdrdvdrmedia.com/bluetoot...le-phones.html
) with the 2.5mm out does not work. I can hear the caller just find but they cannot hear me at all. I am sure somebody smarter than me with good soldering skills could make a cable that would allow it to work.
Trying to hardwire an SMT5600 microsoft smartphone using this adaptor did not work. http://www.pocketpctechs.com/main~un...PPCPADPT14.htm
Using this I could hear the caller fine but they couldn't hear me well while stationary and not at all when the bike was started.
I am very happy with the HF800. I may jack around with one of the Parrott Bluetooth kits sometime down the road so I can see on the display who is calling but for now my task is complete.
Feel free to PM me if you want more details.