How do i get sendmail to process mails in /var/spool/clientmqueue? sendmail -q does not work for this directory.
You will need to check what items are in that folder, if it is a qf/df pair, then it probably a failed mail transaction. So something wrong with your setting or mail not going out or to someone or even got rejected.
You also need to know that the normal "sendmail -q" will process the queue every one hour interval. You can do "sendmail -q10m" to make it process the queue every 10minutes.
It will also be good to check the mail queue "mailq -v -Ac", see if its empty or not. If its empty, then those mail in the clientmqueue, must have been the one that are not successful.
To manually flush the queue in clientmqueue:
sendmail -Ac -q -v
Or without -v if you don't want to watch the progress in the console:
sendmail -Ac -q