This server has been experiencing high loads with no apparent reason and a quick look makes qmail look responsible for this.
On 2006-08-13 an Interworx automatic update:
Name Version Type Status
-
qmail 1.03-209.rht90.iworx os
seems to have changed something and it is causing very high server loads, I have had to kill several never-ending concurrent vpopmail (qmail-smtpd) processes but these processes reappear after just a few minutes.
I thought it could be someone trying to use SMTP so I have checked the mail queue but everything looks fine there, so I came to the conclusion this issue could be related to this update.
Any Ideas ???