Matt Shields wrote:
See that link (http://lists.centos.org/mailman/listinfo/centos) at the bottom of these emails? Click on it and follow the instructions.
Assuming that what simon is asking is how to interact with the sendmail mailing list, here is the google groups gateway to the newsgroup. I'm not sure that there is a mailing list.
http://groups.google.com/group/comp.mail.sendmail/topics?lnk=srg&hl=en