http://www.sendmail.org/~ca/email/relayingdenied.html
How do mail.relate24seven.com (65.103.191.30) and
nhpsde.heritage.unm.edu (64.106.114.26) play together? Last host seems
to be queried for both the recipient address @cs.unm.edu (though I do
not see it as an MX entry) and @ relate247.com. Did you configure
nhpsde.heritage.unm.edu to be the smart host relay?
Janu