It's useful to note that this can use up a lot of bandwidth and unless you're on an unlimited data plan can get expensive quickly.
A good friend of mine used regular Treo data for a month when Verizon had him set up as not having unlimited data. Well, long story short, his bill was over $2k. Luckily, they reversed the charges. He told me had temporary heart failure.
I could see BT DUN using large chunks of data -- enough to get noticed (if Verizon wanted to know). I'm guessing that a company like Verizon is too busy with all their businesses to worry about a few renegades sucking up bandwith.
Have you heard of anyone getting a slap on the hand for this?
-Chris