alias domain and undeliverable mail reports

[c . baegert-listes [Permanent Link]]

Hi,

I use virtual domains to handle several domains for all the adresses on the 
same account. But there's a problem with this configuration, because if a 
spammer sends a mail to randomemail AT domain1 DOT com, postfix answers that 
the 
user does not exist, without sending a mail (perfect), but if he sends it to 
randomemail AT domain2 DOT com, postfix sends 250 OK, forwards it to 
randomemail AT domain1 DOT com, and then an "undeliverable mail" is sent to the 
spammer (and of course, its address doesn't exist...). This is the most 
important part of the load of my mail server !!!

my main.cf :
virtual_maps          = mysql:/etc/postfix/mysql-virtual.cf

Any idea ?

Regards,
-- 
Christophe