I have just installed a mailing list manager (Mailman) for use with my Postfix installation (which has just been upgraded to 2.5.5). I have patched Mailman to use the XVERP option on MAIL FROM.
This works, but I was surprised to see that when the recipient address provided by Mailman is rewritten by Postfix' virtual_regexp, then the recipient address that Postfix encodes in the envelope return path is the rewritten address, rather than the original subscriber address that Mailman knows. Since mailing list software using XVERP needs to recognize the address from the envelope return path as being equal to the subscribed address, would it not be better to always use the raw address from RCPT TO, rather than the rewritten one, when creating the VERP'ed return path? I have not tested this with the 2.6 experimental release, but the release notes say nothing about VERP, so I assume the behaviour is the same in 2.6. (This is not a serious problem for me: the addresses that are rewritten in my installation are in practice local addresses and it is extremely unlikely that they will bounce. But it surprised me.) -- Jesper Dybdal, Denmark. http://www.dybdal.dk (in Danish).
