It was thus said that the Great Pete Turnbull once stated: I've had to harden sendmail against some of these attacks (by modifying sendmail.cf [1]). Assuming that ``sean(a)conman.org'' (my spam catching address) is the one being targeted, and ``armigeron.com'' (which I do some side work for from time to time) is the host being used for the relay, I've had to check for: "sean@conman.org"@armigern.com sean@conman.org@armigeron.com "sean%conman.org"(a)armigeron.com sean%conman.org(a)armigeron.com "sean(a)conman.org"%armigeron.com sean(a)conman.org%armigeron.com There may be a few more obscure methods, but I think those where the only ones I needed to protect against. -spc (Been there, done that, used be listed on MAPs or ORBs or one of those systems ... ) [1] I modified the current senamil.cf because I had modified the sendmail configuration to support virtual domains (before sendmail had included support through virtusertable[2]) and using a more current sendmail.cf would have removed such modifications. [2] I decided not to use sendmail.cf's virtusertable because the method I used was more flexible (each domain has their own file) and because a customer of Armigeron had the ability to modify the email addresses for their domains (whereas using virtusertable, *every* domain is in a single file). Plus, a recipient email address can have more than one destination address (another restriction of virtusertable that requires some nasty workarounds).