I have update sys. To 10.6.4 combo with out problem but not stable than 10.6, replace the Intel wifi to dell pci E. dell 1390 BCM94311 (Lenovo do not let we replace the system
Part, you have to patch the bios otherwise will get the error code will not boot) ….no kext. Need for new wi-fi work as Mac airport. So far so good for T61.

Best. Kimgift