On Wed, Apr 01, 2015 at 08:30:56AM -0700, Michael Fox wrote: > > > /^Received:\s+from\s+domain\.example\s+/ ... > > I may be the least expert on this list so take what I say with a grain of > salt. But this observation may be helpful: > > I have seen several cases where there was no space between the > "Header-name:" and the header value.
I am assuming that the header in question is created by the OP's Postfix system and captures the HELO name used by an external client. Postfix always inserts a space. If this header check is intended to match "far upstream" headers, then one might indeed allow for missing white-space, but it is extremently unlikely to be worth bothering. -- Viktor.