same installation process on 4 wrt54GS
2 works fine
2 fall down after openwrt-wrt54gs-squashfs.bin tftp but works after jffs2 tftp

so i use jtag method to recover between pin 5&6
tftp of WRT54GS_3.37.2_US_code.bin    bingo it works

special kinksys html info page says
Vendor:LINKSYS
ModelName:WRT54GS
Firmware Version:v3.37.2 , Nov  9 2004
#:000
Boot Version:v3.4.2
CodePattern:W54S
Country:US

RF Status:enabled
RF Firmware Version:v3.37.2
RF Domain:US (channel 1~11)
RF Channel:6
RF SSID:linksys

-----Dynamic Information
Hardware Version:2.0

before enable-boot-wait by ping method i obtain this nvram show listing html://gauthier.remi.free.fr/sortie-nvram.txt

if i re use tftp with squasfs => broken again
if i tftp with jffs2 image => it works, i can connect via telnet. But after reboot telnet and ssh don't work.
It only works if i use linksys-fixup.sh before tftp of squashfs rc3

tftp 192.168.1.1 PUT openwrt-wrt54gs-jffs2.bin

telnet 192.168.1.1

mtd unlock mtd4
mount_root

reboot
passwd

scp linksys-fixup.sh root@192.168.1.1:/tmp/.

root@OpenWrt:~# ./linksys-fixup.sh
HW type: BCM4712+BCM5325E
nvram set sdram_init=0x010b
nvram set sdram_config=0x0062
nvram set clkfreq=216
nvram set sdram_ncdl=0x0
nvram set pa0itssit=62
nvram set pa0b0=0x15eb
nvram set pa0b1=0xfa82
nvram set pa0b2=0xfe66
nvram set pa0maxpwr=0x4e

nvram commit

ipkg install webif

web update openwrt-wrt54gs-squashfs.bin

passwd

bingo i have my wrt54GS with squashfs rc3 openwrt.

where is the problem with this model ?
have you some explanation ?

can i really use it after this method ? it seem to be very unstable. If nvram setting disappear :-(

i have test more and more combination to deliver this post.

thank's a lot