There are something wrong with lock file inside /var/qmail/supervise. Try reinstall with 'yum reinstall *-toaster; sh /script/fixmail-all'. And or try 'qmailctl stop', wait 10 second and then 'qmailctl start'.
Yes, service config for qmail on 15 have something wrong and then 16 fixed it.
For squirrelmail issue, try 'sh /script/fix-chownchmod'.
Mustafa always writing to do so (and I've done it all before I wrote about it and they do not fix), but it does not help. It did not help in the previous update and present.
In a new installation I did yesterday are the same errors. The previous update your install in the test was the same.
The last update that I was able to fix it was 6.5.0.f-2013031812.
Restart qmail with:
/etc/rc.d/init.d/qmail stop
/etc/rc.d/init.d/qmail start
If still not working try killing with killall -9 clamd beetween stop and start
Spacedust recently gave Mustafa data to the server and does not fix anything. He wrote to get around to perform the same command as above. They do not fix anything.
After all, it is stable and the final version should work properly after installation of each and do not swarm of bugs. Since the test versions are unstable.
Currently it does not work properly which is associated with the mail.