Definitive Guide to Smtp and notifications, handsup!

Lo looking for the howto for enable the nagios install to use a remote smtp server for sending/replaying notifications.

could i get an example plz

i inherited this from another it guy who installed 2.x on a client site and that site has a gateway to gateway vpn to my network on which there is a slackware linx box with sendmail on it.

it’s config’d to allow relaying.

any thoughts??