[Dovecot] Dovecot 2.0+LMTP: Legal MAIL FROM rejected?

[Bernhard Schmidt]

Hi,

I run Dovecot 2.0.13 fed by Postfix over LMTP. Today it rejected one
mail Postfix and Amavis accepted, generating a bounce. It was just a
spammail, but I think the sender address is legal according to RFC5321
and should be accepted. I don't like generating bounces, email should be
either rejected by postfix/pre-queue-amavis or delivered.

Jun  6 12:32:47 mail postfix/qmgr[840]: 991FC240DB: from=<admin <admin at kl38000.com>, size=8427, nrcpt=1 (queue active)
Jun  6 12:32:47 mail amavis[27046]: (27046-06) FWD via SMTP: <"admin <admin"@kl38000.com> -> <user at domain.com>,BODY=7BIT 250 2.0.0 Ok, id=27046-06, from MTA([127.0.0.1]:10025): 250 2.0.0 Ok: queued as 991FC240DB
Jun  6 12:32:47 mail postfix/lmtp[4710]: 991FC240DB: to=<user at vmail.domain.com>, orig_to=<user at domain.com>, relay=pop3.domain.com[::1]:24, delay=0.24, delays=0.09/0.11/0.03/0.01, dsn=5.5.4, status=bounced (host pop3.domain.com[::1] said: 501 5.5.4 Invalid parameters (in reply to MAIL FROM command))

It looks like dovecot/lmtp does not accept an address with quoted
localpart that contains a space

mail from:<"admin admin"@kl38000.com>
501 5.5.4 Invalid parameters
mail from:<"adminadmin"@kl38000.com>
250 2.1.0 OK
mail from:<"admin<admin"@kl38000.com>
250 2.1.0 OK

Bernhard