Posted by Andy Hassall on 12/16/05 21:17

On Fri, 16 Dec 2005 08:05:21 GMT, Tim Roberts <timr@probo.com> wrote:

>>SMTP is supposed to support a minimum of 50 addresses for a given
>>message. It is not guaranteed to go higher than that.
>
>Where did you read that? Wherever it was, I wouldn't trust anything else
>that it says. RFC2821 clearly says:
>
> The second step in the procedure is the RCPT command.
> RCPT TO:<forward-path> [ SP <rcpt-parameters> ] <CRLF>
> ...
> This step of the procedure can be repeated any number of times.

Perhaps the previous poster is misquoting RFC2821 sec. 4.5.3.1 "Size limits
and minimums":

" recipients buffer
The minimum total number of recipients that must be buffered is
100 recipients. Rejection of messages (for excessive recipients)
with fewer than 100 RCPT commands is a violation of this
specification. The general principle that relaying SMTP servers
MUST NOT, and delivery SMTP servers SHOULD NOT, perform validation
tests on message headers suggests that rejecting a message based
on the total number of recipients shown in header fields is to be
discouraged. A server which imposes a limit on the number of
recipients MUST behave in an orderly fashion, such as to reject
additional addresses over its limit rather than silently
discarding addresses previously accepted. A client that needs to
deliver a message containing over 100 RCPT commands SHOULD be
prepared to transmit in 100-recipient "chunks" if the server
declines to accept more than 100 recipients in a single message."
--
Andy Hassall :: andy@andyh.co.uk :: http://www.andyh.co.uk
http://www.andyhsoftware.co.uk/space :: disk and FTP usage analysis tool

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