Email with Exchange 2k from command line

When our company had some problems with Exchange 2000 on a server a while back, Microsoft had me try e-mailing using HELO or EHLO from the command prompt. I tried this a few times, sometimes working, sometimes not. I did not write down how I was doing it though (stupid me). Does anybody know the commands to send e-mail on a WIN2K system to a mailbox on an Exchange 2K server?