[Exim] blocker router

Hi,

I made a blocker router who actually (should) block all emails that not
have an own account. This is been done directly after splitting of the
email through aliases, so that after that step i should be sure that all
emails left are accounts or unroutable. At the moment it really works, but
cause its so "small" i would like to get information if i should add some
more options to be sure.

blocker:
driver = redirect
data = GET_LOGIN
no_more

GET_LOGIN is the SQL query who only gets back an account.

(simplified: SELECT login FROM user WHERE login=$local_part@$domain)

Bye!