To answer my own question, it was the
if error_message then finish endif
line in my filter. Now while supposedly a null sender does indeed
constitute an error message the amount of spamware that uses this
method to bypass some filters is too big to be ignored. A mention
in the documentation of this behavior would be nice.
Also, since this is in the context of a filter transport, a "fail"
will not work, as the messages gets frozen and when thawed will
be delivered (provided you have the filter doing first_delivery
filtering only). So dropping it was the best solution.
Dewa,
<CB>
--
Christian Balzer Network Engineer Engineering
chibi@??? Exodus Communications K.K.
Phone: +81 3 4354 0290 FAX: +81 3 ?? http://www.exodus.co.jp/
