Please help to solve the problem

I have got a zimbra installed on a FC5 and everything running now just go a error message when I click on console's server status:
Message: system failure: exception during auth {RemoteManager:>}
Error code: service.FAILURE
Method: ZmCsfeCommand.prototype.invoke

this also happen to the server that I have installed on the Ubuntu too.
I have check on the zmcontrol status,
everything running, and I have tried to restart the zimbra too but still have the same error message evertime I click on it.
otherparts are Ok no error at all and still running.

And I have try to add additional port of Smtp
in the postfix
but it does not work.
Can anyone give me some suggestion on the correct way to do it. As most the local ISP have block he 25 port

Can anyone suggest how to deal with this problem.

Many thanks,