In message 1115622690.10065.15.camel@localhost you wrote:
i set bootargs blank, and set CONFIG_CMDLINE="root=/dev/nfs nfsroot=172.16.6.79:/opt/montavista/cee/devkit/arm/v4t_le/target ip=172.16.7.180:172.16.7.180:172.16.6.1:255.255.254.0 console=ttyS0,115200 mem=32M" when booting from ram and flash.
I bet you did set bootargs, and if just to the pre-configured value.
I really don't understand why you don't provide the information I asked for. You can as well stop posting your questions then because I won't be able to help anyway.
i used tcpdump on the nfs server, and found no packets from my board when booted from flash.
Maybe you should read the FAQ, especially http://www.denx.de/twiki/bin/view/DULG/EthernetDoesNotWorkInLinux
Best regards,
Wolfgang Denk