Please help me, a problem in qmail!!

[cool dragon]

Title: ÇçÀÊ

Dear Sir,   I am very sorry to taste your time with such problem. But it troubles me for a long time.I am raring to have a help from you.   I am building a mailserver in local net in redhat, using qmail. After I configured the qmail  and start it, I can conect to the mail   server from outlook, but when I try to send a mail form the outlook to myself, It is failed, I checked the mailog in /var/log in the   mail server, it shows like the following:   "alert: unable to opendir to do, sleeping.........."   could you tell me what the problem it is.   Thank you very much   Regards.   Jianlong Chen               '