Apple's "telnet" is broken.
"telnet" is a program that lets you make an unencrypted login to another host on an arbitrary port. It is a useful testing tool, for making sure that the firewall you're working on is working; or for making sure the service you are working on is answering.
Normally you give it a hostname and a port number. Simple.
Only, with apple, if you give it port 25 ("SMTP"), it decides not to do a regular host to IP lookup, but instead... does a MX record lookup. As in, it goes somewhere other than where you told it to go.
Jason-Feslers-computer:~ jfesler$ telnet gigo.com 22
Trying 216.218.228.114...
Connected to gigo.com.
Escape character is '^]'.
SSH-2.0-OpenSSH_4.5p1 FreeBSD-20061110
^]
telnet> close
Connection closed.
Jason-Feslers-computer:~ jfesler$ telnet gigo.com 25
Trying 216.218.228.118...
Connected to mx2.gigo.com.
Escape character is '^]'.
220 goat.gigo.com ESMTP secondary mx only defers/rejects. postmaster@gigo.com
^]
telnet> close
Connection closed.
Jason-Feslers-computer:~ jfesler$
Update: This happens for ssh, nc as well. As it turns out, Apple's doing this on quite a bit..
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