janszoon - i haven't responded since i don't use an n900 anymore (mine died a while ago). i'd rather not give you a possibly bad response if someone else is able to help you.

with that said, my 2 cents is If you are getting the tethering activated message, the n900 may be setup properly. it's hard to say for sure obviously, but you may want to test it using a computer connected via bluetooth to see if that works.

the other thing you may want to check is that your device is the one connected to bnep0. if you have multiple devices connected to your phone, the bluetooth interface may be different (eg bnep1). you can use the "ifconfig" command as root to check if you have more than just the one bnep0 interface defined.

fyi - there was a newer version of the script that starts up your grps connection if you don't have an active internet connection up (though you'll need to manually modify a setting--see the comments in the script for more info). also, if you've installed dbus, you shouldn't need to run the start or stop command yourself (the same/similar activation messages should appear as soon as you connect a bluetooth device as the ones you get when running the tether.sh script manually).