> 1) Some new releases of sendmail install the program as group kmem. > I can't see any good reason for this Most likely it is so that sendmail can determine the load average. It has a feature that it will start queueing everything (rather than delivering immediately) at one load threshhold, and another threshhold at which it will begin refusing connections altogether. On some systems, there is a system call to get the load average through the kernel. On those where there is not, it is necessary to read /dev/kmem to get this information. --Greg