Well I still don't know why the noreceipts option in the privacy flags isn't work. But, the computer that is acting as my spamtrap is only a spamtrap so it should never ever send any mail out. As a quick and dirty hack I defined a Smart Host with a mailer of local:nobody. It works, but I'd like noreceipts to work since I don't want my real mail servers sending receipts to spammers. I turned off automatic image display in my mail program to keep the spammers from knowing they found a real address. I don't like that they can use my own mail server against me to track that they have an address that they can deliver to.