> that has indeed put in CRLF pairs (looking at Wireshark). So > clearly I'm barking up the wrong tree as to the precise problem...
That's usually the case with Internet servers - most of them are very
permissive when it comes to LF or CRLF...
The one notable exception I've found is MS Exchange. That gets very heated
about it - to the extent that I've seen it reject messages that go through
spamassassin (which is very untidy when it comes to preserving
line-endings).
