SMC anti-spam e-mail milter (plug-in) is an software application designed to significantly reduce the amount of SPAM/UCE (junk-mail) you receive. SMC uses a greylisting like technique to stop the junk-mail and a set of dynamic auto "whitelists" for unknown, but legitimate senders. In purpose of anti-virus protection the program can use very popular Clam AntiVirus engine as a back end.