Section of RFC 2822
atext = ALPHA / DIGIT / ; Any character except
controls,
"!" / "#" / ; SP, and specials.
"$" / "%" / ; Used for atoms
"&" / "'" /
"*" / "+" /
"-" / "/" /
"=" / "?" /
"^" / "_" /
"`" / "{" /
"|" / "}" /
"~"
Though some e-mail clients interpret this as invalid.
Any advice welcome.
Yes, it is valid. However, note that it historically has a special meaning
as an operator.
Language lawyer answer: of course it is, that's what the RFC says.
Real life answer: for a long long time, sendmail rewrote mail to a%b@c
-> a@b, from back in olden days when you had to stuff mail through
gateways to get it delivered. Then spam showed up, and the percent
hack was grossly abused to relay spam.
So the reality is that if you try to send mail to an address with a
percent in it, a fair number of places will just reject it. Unless
you like wearing a "kick me" sign, don't use it. Most addresses with
percents are now lame attempts at spamming, so you won't be doing
anyone any favors by accepting them.
Incidentally, exclamation point has roughly the same problem, due to
its historic use in uucp gateways. For a long time, the way to get
mail to me from the Internet was ima!johnl@CCA.
good advice, but I understood the question to come from someone
validating e-mail addresses, e.g. in a client or a web form. in my
opinion, such validation should make no value judgements on the
cleverness of the address. some people may actually be using UUCP
style routing still, and you shouldn't care -- the meaning of the
local part is nobody's business other than the server handling the
domain.
--
Kjetil T.
>>Is the percentage "%" valid in email addresses?
>
>Language lawyer answer: of course it is, that's what the RFC says.
>
>Real life answer: for a long long time, sendmail rewrote mail to a%b@c
>-> a@b, from back in olden days when you had to stuff mail through
>gateways to get it delivered. Then spam showed up, and the percent
>hack was grossly abused to relay spam.
>
>So the reality is that if you try to send mail to an address with a
>percent in it, a fair number of places will just reject it.
Unfortunately, not all. I recently (maybe 6 weeks ago) received
several copies of a spam that was explicitly routed through about 20
relays in 3 domains. They all started in the same place but each went
through the set of relays in a different order.
I really hope it wasn't the start of a trend. I did think most mail
systems rejected explicit routing these days.
>Unless
>you like wearing a "kick me" sign, don't use it. Most addresses with
>percents are now lame attempts at spamming, so you won't be doing
>anyone any favors by accepting them.
>
>Incidentally, exclamation point has roughly the same problem, due to
>its historic use in uucp gateways. For a long time, the way to get
>mail to me from the Internet was ima!johnl@CCA.
George
--
for email reply remove "/" from address