I think the answer is yes, however, I believe it would require installing some hacked firmware on your WRT54G:
http://toys.lerdorf.com/archives/19_54G ... Wires.html
Basically I would hook your BEFW11S4 to the cable/dsl modem and hook your clients up to your WRT54G. With the hacked firmware you should be able to put your WRT54G into client mode so it will talk to the BEFW11S4. I haven't done this so it is all speculation. I think the article mentions using the SVEASOFT hacked firmware but I personally wouldn't use their firmware for moral reasons. Not sure if there is another hacked version already out there that will do the same thing (I'm guessing there is).
[GPL zealot rant]
I read over
a thread on sveasoft's forums and I am not too keen on the main dude's
attitude toward the GPL. He makes excuses for not releasing code for all of his binary releases and call people ungrateful zealots who question him on it. I believe he is ungrateful for all of the hard work of all of the people who placed their code under the GPL to even make what he is doing possible. There are millions of lines of GPL code in that firmware and he hacks a few lines and all of a sudden he is god. If you don't accept the license, don't use the code. He is more than welcome to write his own kernel and his own compiler and supporting development tools. The attitude is nauseating. It's not like he has to include the entire source tree. Making a patch of the differences between the stock LinkSys source and his own is trivial:
$ diff -Naur linksystree sveasofttree | gzip > sveasoft.patch.gz
I don't believe there is anything wrong with pointing to the linksys download site for the bulk of the source, and then offering the patch produced by the above command on his own download site with instructions on how to apply the patch (zcat sveasoft.patch.gz | patch -p1). The funny part is that LinkSys didn't originally supply the source code. It wasn't until they were
called on it by the FSF that they made the source code for the firmware available. It was the GPL that forced them to release the source. If not for the GPL, SVEASOFT and other hackers like them (including me) would not be in a position to modify the code and make our devices more usable to us. Instead of praising the GPL and thanking those who released their code under the GPL, they oops all over the GPL and the people who wrote the code used as the basis. Even worse, they are now taking donations for behaving this way. Pure scum. I wouldn't mind the donations or even charging as much as they want as long as they give credit to those who truly deserve it and follow the terms of the license that those poeple chose, you know, the license that allowed SVEASOFT to even have the ability to do what they are doing.
I have done my own hacking on the Linksys firmware but I did not release it at all because I don't have the bandwidth. I would not release the binary without the source because I respect the GPL and I respect the authors who placed their code under the GPL. I will not be using anything from sveasoft and I'm sure that's fine with the guy who runs it as I am certainly one of those "GPL zealots". The guy's attitude reminds me a lot of Darl McBride.
[/GPL zealot rant]