Sendmail: rejecting new messages

[spddmon]

Hello all.
I've been bad, I played with my server so much, now it is mad. ps -ef indicates "sendmail:rejecting new messages".
I temporary disabled iptables and ipchains which includes my custom firewall rules, thinking maybe I messed that up, bu still the same. I recently added a second NIC to use on LAN, but disabled that too, and the problem stayed.
What can I mess with next to try to rectify this? Any help?
Thank you.

 

[spddmon]

Ok, I found the problem. It was so stupid I can't believe I couldn't detect it earlier. I ran out of disk space on /var, which you know contains spool/mail, mqueue, vbox ..etc.
Well I freed up a little space and now it is working. Now I am trying to add another HD and see if I can mount it as /var.
If anyone has any tips on doing this, thank you in advance.