How to determine a card's ID for editing the info.plist file was originally posted here in the Jan. 31st, 2003 news page, where a PB owner used that trick to use an older Linksys 802.11g card with (pre-v3.1) Airport Extreme extensions. (Linksys has often changed their chipsets in their 802.11 cards, so that older info may not work anymore with their current 'versions'). That post gave me all the info I needed on how to get the ID's for this MS card using IOreg.

I installed one of the MS cards in a MDD G4 tower after first removing the original Airport card. (Disconnect the AC power cord before removing or installing anything.) Booted into 10.3.4 and ASP didn't list the PCI card. (Rebooted twice and checked again - still not shown.) Decided to boot to a 10.2.8 volume and it did show up in ASP.
Then ran an ioreg dump from the terminal to get the Microsoft card PCI ID strings (which are "pci1414,4" and "pci14e4, 4325") for editing the plist.info file inside the /System/Library/Extensions/AppleAirport2.kext file. First make a backup copy of the original AppleAirport2.kext file (option drag a copy of the file to the desktop or another drive/folder for instance.) Then Cntl+click and 'show package contents' on theAppleAirport2.kext file (or right click if you have a 2 button mouse) - the info.plist file is inside the contents folder.

You have to be root to edit the file normally, but assuming you're logged in as the system admin user, you can do a "get info" on the file, then change the owner to you in the permissions menu section of the file info panel. (Click on the lock, then authenticate by entering your password, then you can change the ownership menu from system to your username.)
After doing that, here's a quick guide to the edits:

1. Drag the info.plist file to a text editor (textedit, bbedit, etc.) to open it, then look for the section heading:
   "<key>Broadcom PCI</key>"
2. In that section there will be another key named "IONameMatch", with either 2 (seen in the 10.2.8 file) or 3 (in the 10.3.4/Airport 3.4.2 file) <string> IDs. I replaced (edited) the two ID strings ("pci106b,4e" and "pci14e4,4320") with the 802.11g MS card IDs ("pci1414,4" and "pci14e4, 4325")
3. Save the edited File
4. From the Finder, do a get info on the edited file and change the permissions back to "system".
5. Reboot
   (easier than using the terminal to do a "sudo kextload /System/Library/Extensions/AppleAirport2.kext")

With the edited file, the MS 802.11g works perfectly in both 10.2.8 and 10.3.4. (Becomes the "Airport" port in Network Prefs instead of the Apple Airport card which was removed before installing the PCI card.)

Since any updates to Airport Extreme drivers will overwrite the edited file, I keep a backup of it (as well as the original unedited version).

Browsing, downloading, Software Update downloads and printing to the shared USB printer attached to an Apple AirportExtreme base here all work fine.

Since the MDD (and older towers) don't have an Airport Extreme slot, this is a nice (and cheap) upgrade if you have an otherwise 802.11g base/network. Another plus the signal strength seems better with the PCI card's antenna. But remember none of these 802.11g PCI adapters are supported in older OS's like 10.1.x, OS 9.x and before unless there's some 3rd party drivers I don't know about.

And if using some other Broadcom chip based cards like the Belkin F5D7000 mentioned in Monday and Wednesday's news pages, you don't need to edit the plist.info file, although they usually cost $20-30 more than what I paid for the MS card.

Motorola Card Alternative: (See update below before buying)
I had to drive out of town Saturday to visit an ill relative and stopped at a Walmart along the way to pick up a card. While there I noticed they had Motorola 802.11G PCI cards (WPCI810) for $39.63 - that was a few pennies less than I paid for the Microsoft card (which needed info.plist editing noted below), and I remembered Motorola was listed on the Broadcom 802.11g products page (linked in Thursday's news) so I bought one to test. I installed it in a Digital Audio system (removing the original Airport card first) and it was plug and play in both 10.2.8 and 10.3.4 (both had the latest Airport updates for each OS).
(UPDATE: See the updated notes on 2 different versions of the Motorola card in the Feb. 23rd, 2005 news page. Like many network cards sold by primarily PC market companies, the chipset can change at any time - so if in doubt, buy from a retail store that allows returns.)

Related Articles/Info:
There were several other reports on Airport 3.1-3.4.x Compatible 802.11g PCI and PCcard adapters ealier this week. See the July 26th-30th News Summary page. The FAQ's Networking section also has previous reports on Airport 3.1+ compatible cards/adapters, Drivers for other cards and reports on other options for older Macs w/o airport card slots (like Ethernet to Wireless bridges, USB adapters with Mac drivers, etc.)