i m using AM300 also, juv bought wrt54g yesterday and i faced this problem, error msg : can not get ip address from PPPoE server;
ermmm...
my setting is
AM 300
Encapsulation : Bridge mode only
DHCP:off
DSL modulation L: Auto
IP : 192.168.1.2

WRT54G
login required, PPPoE mode
DHCP: off
IP:192.168.1.1

i cant connect to the internet..
anyone using these modem and wifi router? need help