I've installed mailman 2.1.9 via the yum repository on Centos 5
according to the Redhat documentation. The web interface is working,
however emails sent to any list are being delivered to but not processed
by mailman. There are no entries in the mailman logs to indicate
anything is happening. The postfix log says the messages are being
delivered to the lists. The mailman service is running and the mailman
cron jobs are processing.