[ubuntu-in] Sharing Internet from within Ubuntu

[Ramnarayan.K]

Hi

Am accessing the net of an old laptop running Ubuntu 7.10. This is the
only machine that can access the net via a BSNL WLL (CDMA) phone. I
want to share this internet with other machines that have moved on in
life and are running higher versions of Ubuntu.

TO share the internet i have a Linksys wrt54gl router (with both wifi
and ethernet).

My old laptop has a ethernet port - which means i should be able to
connect it to the in port slot of the router. Question is how ??

An add on question is from within the router what do i do for it to
pick up the internet (the router itself is running freifunk /openwrt
firmware).

would appreciate the help.
ram