sendmail + router
i have what i hope is a fairly simple problem, but i'm just not able to solve it! here's the low-down: i have a network, consisting of 4 clients behind a router (slackware 8, 2.4.5 kernel, iptables + netfiltering) and i have sendmail running on a client which is running slack8 on the 2.4.17 kernel. i can receive mail fine through the router - as the router forwards all incoming requests to my sendmail client on port 25 - however, i can't send mail at all through pine or any other program. i'm sure it has something to do with my router, since when i send mail through the router, it reaches its destination just fine. is there anything i'm missing with iptables?
i appreciate any help you guys can offer. :-)