Using a blackberry bold 9700 as an bluetooth modem

A blackberry bold 9700 can be used as a generic bluetooth modem. That is, without the use of the blackberry manager software.

The trick is to change the phone number that is dialed.
The general phone number to connect to a UMTS (3g) network is *99#, but in the case of blackberry it should become: *99***4#.
Using this phonenumber in combination with a generic bluetooth modem (which is available after pairing) one should be able to make successful dial-up to a 3g network, using the blackberry as a tether device.