R40 Bluetooth upgrade, modem not functioning after.

[grspider]

Hello,
I've got an R40 (type 2722ABG) on which I decided to replace the original modem card with a BMDC200 bluetooth/modem combo card.
The bluetooth operates as expected, however the (new) modem can not be operated although it is properly recognized by XP. I'm using the standard "Agere Systems AC'97 modem" as stated in the IBM's site.
XP will give me a message that it can't open the port where the modem is attached, and of course the diagnostics fail as well.
Any ideas of what might be the problem? Any help would be much appreciated because i've run out of ideas on the subject.
Thank you for any info you can give me.