I'm pretty sure that Sprint disabled DUN on the PPC-6700 to get laptop users to buy their wireless cards. There is a program on the install disc that comes with the phone, called wireless modem or whatever -- some people claimed success at wireless DUN. I never did. I think it's because of the bluetooth stack on my laptop, an HP L2000.

However, even when DUN didn't work, the bluetooth active sync did work on my laptop and it seems like the PDANet application tricks the phone into using the sync function to transmit data. I'm not sure why the phone always has to be reset but that has always been my experience.

I've been able to stay connected for hours, so I'm not sure of what is causing your problem, but i don't let the phone get very far away from the N800. I'm sure you'll be able to find something that works.

I'm probably going to get rid of the PPC 6700 soon, but I want to find the smallest phone I can get that supports DUN without any workarounds.