[exim] Unrouteable address ERROR

Grettings to everyone! Today i modified a bit my exim.conf in such a way,
that first to check virtualusers then aliases..i bet it sounds weird. Here
is my config:

 virtual_user:
  driver = redirect
  allow_fail
  allow_defer
  data = ${lookup mysql{ SELECT maildir FROM users \
          WHERE id='${quote_mysql:${local_part}@${domain}}' }}
  directory_transport = address_directory
 # unseen

mysql_aliases:
  driver = redirect
  file_transport = address_file
  pipe_transport = address_pipe
  data = ${lookup mysql{SELECT sendto FROM aliases \
          WHERE (username='$local_part' AND domainname='$domain') \
          OR (username='*' AND domainname='$domain')}}
#  no_more

To make message to pass through virtual_user down to aliases, i have put
UNSEEN word..everything is good, messages are working and aliases too, but
an error message is generated with "Unrouteable address ERROR" back to
the sender. How can i accomplish that and not get that messages???

Best regards,
Oleg R.