The man page doesn't tell, so I wonder if vacation follows RFC 3834? Regards Harri
Harald Dunkel writes ("Bug#1027129: does it follow RFC 3834?"):
IDK, I'm afraid. Why do you ask ?
It's a venerable program which has been used for many years by many
people, without generally causing troublesome mail loops etc. It
predates RFC 3834 by a considerable margin.
Ian.