I have a Linksys WRT54g running DD-WRT. The router is accessing a
network requiring a proxy server. So far i configured all my clients to
use that proxy, but I would like to use the proxy without the clients
knowing it is there.

I googeled a bit and only found a manual to set up a transparent proxy
using a computer as proxy.

Is it possible to configure the DD-WRT to be the transparent proxy
forwarding the requests to the real proxy?