Install on Debian and Zimbra 4.0.4, cannot send mail but postfix is running...but when I type mailq:

postqueue: warning: Mail system is down -- accessing queue directly
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
060C34DC0D7 325 Thu Nov 23 06:10:03 zimbra
zimbra

5A62B4DC0DF 325 Thu Nov 23 06:50:02 zimbra
zimbra

2C3D64DC0E1 325 Thu Nov 23 07:00:02 zimbra
zimbra

F39524DC0E2 325 Thu Nov 23 07:10:03 zimbra
zimbra

392184DC0E4 325 Thu Nov 23 07:20:02 zimbra
zimbra

0778E4DC0E5 325 Thu Nov 23 07:30:03 zimbra
zimbra

F35CB4DC0E6 325 Thu Nov 23 07:40:03 zimbra
zimbra

Pls help...