The Red Hat 9.0 (Small) distro has been updated to contain a fix for sm-client, part of sendmail, failing to start.

If you're using the RH9 small distro and see this when starting sendmail:

Starting sendmail: [ OK ]
Starting sm-client: No local mailer defined
QueueDirectory (Q) option must be set

or this in your syslog:

Jun 24 17:05:04 li-20 sendmail[1157]: starting daemon (8.12.8): SMTP+queueing@01:00:00
Jun 24 17:05:04 li-20 sm-msp-queue[1164]: NOQUEUE: SYSERR(root): No local mailer defined
Jun 24 17:05:04 li-20 sm-msp-queue[1164]: NOQUEUE: SYSERR(root): QueueDirectory (Q) option must be set

you should execute the following commands, or re-deploy the RH9.0 image to your Linode using the Distro Wizard.

cp /etc/mail/submit.cf.bak /etc/mail/submit.cf
/etc/init.d/sendmail restart

-Chris