Bluetooth nightmare

Okay, so ive got meself an ISDN modem (for im in Germany, where they have got all hung up on ISDN lines for some reason, and although its cheap and easy to upgrade to T-DSL, they havnt... )

umm, anyway.. It says it has Bluetooth compatibility.. and it seems that it does.

Our bluetooth connection software that came with the chip (its a sony vaio blutooth umm,... tooth ) says that its found the ISDN access point, but for some reason, and ive conected to it in modem mode...but for some reason, my OS isnt recognising it..

I can still easily enough connect to it via USB and go on the internet via that, but the isdn outlet is on one side of the room, and the lappy is on the other!

Do you need some sort of driver for it? If you did, then why didnt it come with one and why isnt there one available online?

Also, whats puzzling me is why isnt my OS detecting it... Its mapped to COM 5, and i would have thought when i connect it i would get a "new modem found" dialog come up... or somthing...

Incidentally, Sony Vaio, mit Windows XP Pro, und ein Pentium vier M, und auch eine W-Lan Karte.

Oh yes and also it might help (slightly) to know the modem thing itself..

Teledat X120 bei Deutches Telekom, a.h. "T" also, nicht so nutzlich.. ummmmmm...... i mean, aka T but not so useful...

Anyway.. it would be quite useful to work this out... but its not "mission critical"