if_em and ibm thinkpad T40

I have an IBM T40 that has an onboard Intel GigE card. When the em
driver tries to probe it, I get "The EEPROM Checksum Is Not Valid".
Adding a printf, I discover the checksum is 0x08b8 (not the 0xBABA
that is documented in the headers). Anyone else seen any problems
with this? I'd really rather not have to drag around a USB ethernet
device.

-gordon