T41/42 wireless question

[serpico]

I'm looking to buy a used T4x. I know that all T43s come with 802.11 a/b/g. But it seems that some T41 and T42 models come with a/b/g while others are only b. I know I can swap out the mini-pci wireless card (these are the Atheros cards that go for ~$20 on ebay, right?), but I'd rather not bother.

How can I tell which 41/42 models have a/b/g?

[RustyMuppet]

T42 model 2373 has g