On Mon March 14 2005 09:00, Tony Finch wrote:
It does depend on a reasonable expectation of minimal
re-ordering, but that is true almost all the time.
Four and a half years ago I looked in detail at 34 email transfer
products; several of them reordered or otherwise mangled message
header fields. A certain breed of developer hears "name-value
pairs" and thinks "database"; unless pains are taken to preserve
ordering, a database approach results in (pseudo-)random
rearrangement of fields. Unless direct sending from originator
MUA to recipient MX MTA is used (and even sometimes then),
mangling by intermediate MTAs is not under control of either
sender or recipient; it just happens.