In the 2.6.26-x kernels, there were two sysctl options that enabled me to get blinking LED's with my wireless.
They were dev.wifi.0.ledpin and dev.wifi0.softled
I've been looking through the 2.6.27 kernel (including the vanilla ones from kernel.org) and haven't been able to find the replacement if one exists. It's a fairly trivial thing, and I think it was more than a fair trade to get support for the AR5007EG cards in return for losing the LED but I'm curious if there are options--I'm not a programmer, so I'm guessing it's been replaced with something that I'm missing.
Thanks for any input.