Use this info at your own risk and read their instuctions to have a successful firmware update for your specific model should you choose to do this.
This info is for anyone or the wrt54gx2 needing help. " linuxn00b "
We both suspects that the linksys firmware and wpa2 could be the bug in the wifi router or just plain the firmware of the router as even OSX 10.4.9 has issues connecting with WPA2 mixed mode , they still need to update their OSX LMAO but as I have tested it works fine here in 3.4e or later on both ipw3945 / bcm4311mcg Dell cards.
Here it is: http://en.wikipedia.org/wiki/WRT54G
There is several open source linux firmwares to replace several wifi routers firmware with like I used to do with my linksys wrt54gs ver 1.1 .
The purpose of this is to when the manufacturer ignores their lack of security or new security bug in their routers or just don't care anymore then this can be used and as open source / linux it should be fairly stable / up to date.
WRT type models of Linksys some D-link and occasionally some Netgear routers uses similar firmware or the opensource firmware that has all the drivers / parts needed to work on these makes as some do share same chips even over same model number you will find several different chips as we are the guinea pigs for their testing.
Searching with google you will find either by model say linksys wrt54gs or wrt results like hyper-wrt and several others choose the one you feel comfortable with and use at own risk as a bad firmware flash can lead to a brick and then fancy cables are needed on the inside to re-flash this and get it back to life.
PS> If they have a sceenshot or pic of actually how this looks then try it if needed but there is 1 open-wrt that will end you up in root text mode with no gui and you have to custom build what you need from inside this text mode.
Poison of choice for me = http://www.dd-wrt.com/dd-wrtv2/index.php
You would also see that there is several of these that is more maintained / up-to date than others or even same with models in a specific name firmware.
Hope this helps.
Again use with caution and make sure you have the right firmware for your model / make and or read any funny tricks that might be needed to complete this and have a working device afterwards. It is easy but stuff can go wrong.