Feature request to consider: dynamic trusted_networks

[Eric W. Bates]

I would like to ask the community to consider whether this has merit 
(and let me know if it has been proposed before).

I run an ISP, and a number of customers use Verizon DSL (and other 
dynamic IP).  I would just as soon not list whole blocks of Verizon IP's 
as trusted (to avoid DYNABLOCK, et al.).

We have been successfully using a handy bit of perl called 
pop-before-smtp (http://popbsmtp.sf.net/) to maintain a dynamic list of 
valid IP for postfix.  pop-before-smtp tails the log file written by the 
pop and imap daemons and maintains a db file of IP addresses from which 
a valid authentication has been received in the last 2 hours. This is 
used by postfix as an alternative means of smtp authentication (hence 
the name).

Would anyone else find it useful to have 
Mail::SpamAssassin::NetSet->contains_ip() optionally look in a db as 
well as the static list?

Have I found the correct method to add the lookup?
Thanks.