Qmail Logging Problem

[ronron]

Hi!

An employee-PC catched a virus, because he was surfing on "non-work-related-sites"
This virus used the MS Outlook-Installation on the PC, which used my qmail-Mailserver to send over 100.000 Spam Mails which jammed the mailserver.

What I have done so far:
- Cutted the virus PC from the network
- Stopped the qmail service (etc/init.d/qmail stop)
- Deleted the Mail-Queue in the server (This took a few minutes)
- Restarted the qmail service

But I still have a problem, and I don't know how to fix this:

The mailserver does send mails again, however the logfiles are beeing flodded with a message, that I don't understand.

There thousands of messages like that!!
/var/log/mail.info

Dec  3 09:33:21 s15349137 qmail-queue-handlers[9671]: Handlers Filter before-queue for qmail started ...
Dec  3 09:33:21 s15349137 qmail-queue-handlers[9672]: Handlers Filter before-queue for qmail started ...
Dec  3 09:33:21 s15349137 qmail-queue-handlers[9673]: Handlers Filter before-queue for qmail started ...
Dec  3 09:33:21 s15349137 qmail-queue-handlers[9675]: Handlers Filter before-queue for qmail started ...
Dec  3 09:33:21 s15349137 qmail-queue-handlers[9676]: Handlers Filter before-queue for qmail started ...
Dec  3 09:33:21 s15349137 qmail-queue-handlers[9677]: Handlers Filter before-queue for qmail started ...
Dec  3 09:33:21 s15349137 qmail-queue-handlers[9678]: Handlers Filter before-queue for qmail started ...

Please help me to get rid of these messages!
What do I have to do?
Thank you very much!