I like to use extended email addresses, or aliases I can make up on the fly. I mean addresses like [email protected] When someone wants my email address, I make up one which represents the company that asked for it. That way if I get spammed, I can filter that out, and I know who did it. For example, if I subscribe to the ABC newsletter, I can give them my email address as [email protected] and the newsletters will be delivered to [email protected] I tried to modify the postfix and courier config files, but this did not work. But I found its incredibly easy to add an Email --> Global Filters --> Content Filter to do the job through ISPC3. Example: Set Pattern to: /^.*USER[+-].*@YOURDOMAIN.COM.*$/ and Action to REDIRECT and Data to [email protected] This will accept either + or - as the delimiter. I hope this is useful for someone.