ned <ned+ietf-822(_at_)mrochek(_dot_)com> writes:
On 9/10/01 at 1:17 PM -0500, Eric A. Hall wrote:
2) Although any printable character from US-ASCII except colon may
be used in header names, I've never seen any headers use anything
other than alphanumerics and hyphen.
I've never seen one that I can recall. Anyone else?
Hmm. I've seen $ and # and * for sure. I think I've seen % and ^ once or
twice, but it was probably an error of some sort that led to it. I've
seen ( and ) and ; used, but it was _definitely_ bogus usage -- leakage
from GroupWise, if memory serves.
I've seen plenty of underscores.
--
Russ Allbery (rra(_at_)stanford(_dot_)edu)
<http://www.eyrie.org/~eagle/>