[exim] double qualified sender address

Hi

I have problem with routing from authenticated user to the outside.
Sender envelope address gets qualified twice, like:

2008-06-20 05:04:08 1K9Wv2-000Alo-Lx <= "mg@[LD]"@[QD] H=[SH]
[217.113.238.142] U=nobody P=esmtpsa X=TLSv1:AES256-SHA:256
A=dovecot_plain:mg@[LD] S=605 id=200806200500.54147.mg@[LD]

where
[LD] is one of local domains
[SH] is sending host
[QD] is value of qualify_domain

eg. "mg@???

as you may notice user@[LD] is authenticated via dovecot authenticator.

if the mail is delivered, then header looks like
Received: from [SH] ([217.113.238.142] ident=nobody)
    by [primary_hostname] with esmtpsa (TLSv1:AES256-SHA:256)
    (Exim 4.69 (FreeBSD))
    (envelope-from <"mg@[LD]"@[QD]>)
    id 1K9Wjg-000Aja-3k
    for ...

Why is that and how an I fix it to have proper envelope sender?

mails from outside to local users are delivered w/o any problem
regards
--
Marcin Gryszkalis, PGP 0x9F183FA3
jabber jid:mg@???, gg:2532994
http://the.fork.pl