No the WRT54G2 and WRT54G are not interchangeable, they are a fair bit different. However it looks like the WRT54G2 can run dd-wrt (though only the micro limited functionality build), not that I've ever tried on the one* I manage for my parents.

http://www.dd-wrt.com/wiki/index.php/Linksys_WRT54G2

* it has been a pain in the arse as the wifi side of it repeatedly loses devices frown



Edited by andy (22/02/2011 20:55)
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