[dspam-users] DSPAM+POSTFIX not working

We have postfix with many virtual domains in a mysql database.
All our mail domain are under

/home/vmail/domain1/mail1@domain1.com/.maildir/....
/home/vmail/domain1/mail2@domain1.com/.maildir/....
/home/vmail/domain1/mail2@domain1.com/.maildir/....
/home/vmail/domain2/mail1@domain2.com/.maildir/....
/home/vmail/domain3/mail1@domain3.com/.maildir/....

Ando so on...all works well but we want to filter all SMTP email by
DSPAM.

We cannot use ~user/.procmailrc because we have only a vmail user for
all domains....

How can we set up dspam for working with Postfix with this configuration
?
Thanks !

-- 
Dinosoft Italia
http://www.dinosoft.it
Tel. +39 0187 1873615
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