Anyway, the console port did not appear to be a standard pinout. I opened the RJ45 to DB9 connector they provided, and discovered it has this pinout:
|Pin 1||Pin 2||Pin 3||Pin 4||Pin 5||Pin 6||Pin 7||Pin 8||Pin 9|
This is the same as the pinout as I used for the type "A" RJ45-DB9 connector in this article: here.
From my testing, you simply need to make two of the type "A" adapters I mentioned in the linked post, attach a cat5 cable to both ends, and you should be able to connect to the serial port. The Linksys uses 38400 baud - unlike the usual 9600.