Exim ACL Ratelimit database not available

Issue :

Sometimes you may find that you are unable to send mails and will find the following lines in your exim mainlog:
2009-04-05 19:08:41 H=[xx.xx.xx.xx] temporarily rejected connection in ?connect? ACL: ratelimit database not available

Cause :

The exim cache database might be corrupted.

Fix :

You need to delete the following files :
/var/spool/exim/db/ratelimit?
/var/spool/exim/db/ratelimit.lockfile?
/var/spool/exim/db/retry?
/var/spool/exim/db/retry.lockfile?
/var/spool/exim/db/wait-dk_remote_smtp?
/var/spool/exim/db/wait-dk_remote_smtp.lockfile?
/var/spool/exim/db/wait-remote_smtp?
/var/spool/exim/db/wait-remote_smtp.lockfile?
You can do as follows :
rm -fv /var/spool/exim/db/*

and then restart exim :
service exim restart