[Exim] Inter-process database lookup cashing.

    Using some database lookups, you may wait too long
for a connection to database. And Exim will establish new
connection, when a new child process is forked. It's a very
time consuming process. (At least, for Oracle database.)
Or your database can be rather slow (like some Oper-LDAP
backends).
    So, I made a new lookup type, which allows cashing
any queries to any other lookups simultaniously between
exim processes. So, database connection will be established,
only if no data found in cashe.
    I've tested it, as I could, and it seems to be
fast and stable.
    Is anyone interested in it?

        Bye. Alex.