nonexistent virtual account received

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nonexistent virtual account received
\ Tomas Macek (13 Apr 2007)
. \ mouss (13 Apr 2007)

13 msg	How to make postfix use one IP for receiving an...
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Subject:	nonexistent virtual account received
Group:	Postfix-users
From:	Tomas Macek
Date:	13 Apr 2007

Hi, I'm using Postfix 2.2.10, but I hope this would be the same in newer versions.
I have 2 tables with aliases in pgsql. First for mail adress aliases and one for domain aliases - this shlould be OK.
The domains are aliased as follows (lookup configured in alias_domains_maps.cf):

@ourdomain2.cz @ourdomain1.cz
@ourdomain3.cz @ourdomain1.cz
...

When I send an email to a nonexistent mailbox, for example nonexistent, it is rejected just on the rcpt to in the smtp. Works great. But when I sent an email to a nonexistent mailbox in aliased domain, for example nonexistent, it is accepted via 25 port into postfix and then is bounced with "status=bounced (unknown user: "nonexistent")". Why this is not rejected just on rcpt like when sending to nonexistent?

My user alias accounts looks like this (lookup configured in alias_mailbox_maps.cf):
user2 user1
user3 user1
...

And my account map (lookup configured in virtual_mailbox_maps.cf):
user1 /var/accounts/user1
user2 /var/account/user2

What I'm doing wrong? I cannot find the problem from most debugging output, the same like from the virtual(5) doc.

This is my configuration:
-------------------------
virtual_mailbox_domains = ourdomain1.cz

virtual_alias_maps = pgsql:/etc/postfix/pgsql/alias_domains_maps.cf
pgsql:/etc/postfix/pgsql/alias_mailbox_maps.cf

virtual_mailbox_maps = pgsql:/etc/postfix/pgsql/virtual_mailbox_maps.cf

Can anyone help me please. Many thanks
Tomas