at what stage is message_size_limit applied?

7 msg	question on body_checks
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at what stage is message_size_limit applied?
\ Mike Kenny (14 May 2007)
. \ Victor Duchovni (14 May 2007)
. . \ Mike Kenny (14 May 2007)

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Subject:	at what stage is message_size_limit applied?
Group:	Postfix-users
From:	Mike Kenny
Date:	14 May 2007

The subject says it all, I hope.

I have a client complaining that he is being billed for bandwidth due to
attempting to send a mail that exceeds our maximum size. His argument is
that as we did not send the mail for him, he should not be billed for the
bandwidth. My question is 'is this restriction, message_size_limit, applied
during the handshake or is it dependent on counting the bytes received? i.e.
in the first case, the client would not have used the bandwidth, in the
second he would have. I need to get back to him and explain what he used and
what he was billed for.

(the client is not being very cooperative in providing supporting
information to assist me in locating the fault. this is why I am
investigating postfix behaviour rather than log contents)

Mike