[Dovecot] Max number of mail processes

[Patrick Nudo]

Dovecot version 1.1.11.
Error: Maximum number of mail processes exceeded (see max_mail_processes 
setting).

I  can't seem to get rid of these errors.   I  get batches of these 
errors about 4 or 5 times a day.   I  have a cron-job checking for the 
existence of this error and then  I   reboot dovecot when  I  see this 
error, but what is causing this error ?  What  I  am reading on the 
Internet about this particular issue has not helped to resolve the 
issue.   I  would really like to know how many mail processes it thinks 
that it is using at any one instant in time.  Is this possible ?  Maybe 
then  I  can track the reason for the error.