Hi Rossz!
> Except the format of the file can include regular expressions:
> ^.*@spammerdomain.com
> ^susie@???
> I don't remember if the ^ is required or not.
Yes, it is (for regular expressions). To block a complete domain
spammerdomain.com or *.spammerdomain.com
is sufficient, though. Same for full email addresses. Also be aware
that
^susie@???
will additionally match the address susie@??? and others
unless you put a '$' after the regular exp.
Address lists can also contain exceptions. For example, I have been
told by AOL support that valid AOL screen names (and email addresses)
can consist of 5-16 letters and numbers, and must start with a letter.
Therefore
^offer..@aol.com$ # permanent spammer
!^[a-z][\da-z]{4,15}@???$ # valid AOL screen names
aol.com # all others are invalid
aol.de # not-for-mail domain
(in this order!) will first block notorious AOL spammers, then except
valid AOL screen names and finally block all others, along with the
domain aol.de, which is not currently used for email. Dumb spammers
(is this an oxymoron?) frequently use characters like "-" or "_",
which cannot appear in genuine AOL addresses.
This is only for a start, much weirder constructs are possible, see
section 10.13 "Address Lists" of the Exim spec.
Andy