Atomicorp

We are running plesk 10 on CentOS 5 (x86_64)
After a plesk panel update/install last night our server has stopped accepting mail on port 25.
I am sure this update was the issue as initially sw-cp-server was for some reason on port 25 instead of xinetd. After stopping that and getting xinetd to listen in instead it doesn't accept.
Luckily it still accepts on port 587.
Nothing has changed with the smtp_psa file.
iptables shows
2 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:25
3 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:587
4 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:587
5 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:25
I haven't found anything in the maillog or var/log/messages that might tell me what the problem is.
I cannot telnet to port 25.
Is there anything I have missed that could be blocking it?
I have been checking xinetd is listeing in using lsof -i :25 Is there anyway this could misreport?

netstat -alnp | grep :25 shows lots of "TIME_WAIT"
Mail is no longer sending from the server.
maillog shows lots of lines about relaylock

/etc/services is fine.
I'm running out of ideas

It turns out plesk/qmail has decided it doesn't like spamdyke anymore. After removing the spamdyke lines from /etc/xintetd.d/smtp_psa everything was fine.
Spamdyke config tests show everything up as OK so I'm not sure what the problem is.

A while back spamassassin was not working properly and we noticed that in the plesk services management "SMTP Server (QMail)" was showing as red. As soon as we removed the spamdyke line it was fine.
After finding a post on plesk forums that stated you could resolve this by removing the DNSBL on plesk's mail server settings we tried this and it seemed to work.
Now however that seems to make no difference.