Riker is absolutely right in principle in his post that you should not mix hardware and firmware versions. A firmware update for v2 hardware only applies to v2 hardware, not v1. But in his friend defense, Linksys does apparently use the same firmware for different hardware revisions of it’s WRT54G router – the latest firmware for the WRT54G v1.0 is the same file as the latest firmware for the WRT54G v2.0.
http://www.linksys.com/download/firmware.asp?fwid=201