Here is what I have worked out so far...
I have a Toshiba Tecra A6 which did have an Intel 3945 a/b/g miniPCI-E card. I bought a Broadcom 4311 from eBay and installed it then modified the relevant kexts with vendor IDs. I have even added the vendor ID in to AppleAirport2.kext. All permissions were fixed and kext caches removed etc.
The Airport card is recognised and shows up but is unable to find my wireless network. (I have 17" Intel iMac for reference)
The strange thing is this - the NetworkInterfaces.plist shows it as AirPortPCI_MM and not AirPort_Brcm43xx. Is this the big clue? If so how do I get it to use the Broadcom driver? I have tried changing IOClass from AirPortPCI_MM to AirPort_Brcm43xx as it is in my iMac but then card is not recognized at all.
The wireless light does not light despite the switch on the laptop being set to on and there are no BIOS options relating to WLAN.
I am getting close to binning OSx86 on this machine as I can't work without wi-fi. It is such a disappointment as my last laptop (Dell Inspiron 6400) worked flawlessly except for Sigmatel 9220 HD audio and the black screen wake from sleep problem.
This Tecra sleeps perfectly and everything else works great - just wireless.
Does anybody have any ideas? I'm running 10.4.6 and have attached a few bits to help.