I just created a Centos 5 virtual machine in VMware Server with absolutely no optional packages. I only had the first CD... So when I wanted to send an email from the command line, it had no mail server to help its way. The error was: -bash: mail: command not found
The fastest way I could find was:
yum -y install sendmail mailx
About 60 seconds later I was sending outgoing mail like so:
echo test | mail -s "email subject"
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