TMDA notes

Notes on using TMDA (Tagged Message Delivery Agent) for reducing spam. [just started this. -- rgr, 10-Jun-04.]

Confirmation by bounces.: The "Sneaky spam" thread of 3-Feb-2004 on the tmda-users list gives a detailed analysis of a particular case where this happened. In a nutshell, the problem is due to ISPs with mis-configured mailers that send bounces to the "Reply-To:" address; if a spammer uses a forged envelope sender address belonging to that ISP, the bounce message will be accepted as a confirmation. Another message in the thread points to FAQ 1.3 (which has workarounds) and FAQ 7.2