The problem with whitelisting to combat spam...
Note to sys admins: the losers here are Your Users. As edbott says--"if you've got a problem with spam, fix it yourself. Don't push it back on me." Amen. At least a few law firms attempted this sort of system for a while; I'd get a notification back after a post to a LawNet listserv; the notification required that I forward the message to [thisaddress] to bypass the spam filter. I'm certainly not going to bother with that, I remember thinking. If you want a free answer to your question, don't make it difficult for me to respond to you. Your spam problem does not mean you can impose extra costs on me and expect me to pay up.