[exim] Which behaviour is expected/standard from a return-pa…

Hi

i send out emails through exim with a forced return-path to root,
that works
fine, at least when i use tcpdump to check exims relay to the exchange
server. However the exchange server does not appear to use that
return-path value when an email address bounce. This made me think if
a SMTP server should forward the return-path to the next SMTP server?
Or is it free to throw it away and return it to the From: address
that is in the
header ?



JonB