[Nagiosplug-help] send mail notifications

[Nicole Hähnel]

Hi,
after solving most of my troubles with nagios with the help of this mailing
list
it's working very good.
But how do I send mails?
By default nagios uses the mail command, but this cannot send to another
machine?!
Do I need to configure a MTA sth. like sendmail (or procmail?) to send
the mail to our internal domino-mail server?
If so, can anybody help me to configure it?
We have a domino server behind our FW which accepts mails per smtp,
but how do send mail to this server?

Thanks
Nicole