Email Sending Problem to YAHOO

[DeadMan Xia ....]

Hi everybody!!!!!

hope all doing fine ,,,,
well i have configured my Email Server on FreeBSD 6.2 with Qmail, i have
send email to yahoo, hotmail & gmail. On gmail & hotmail, its works quick,
bt at yahoo ,,, its delaying nd mail recieved at yahoo with huge delays. wen
i send email to yahoo, it gives following defferal error,

@40000000466e85af2e894abc delivery 12: deferral:
Connected_to_216.39.53.1_but_greeting_failed./Remote_host_said:_421_Message_from_(
58.65.151.33
)_temporarily_deferred_-_4.16.50._Please_refer_to_http://help.yahoo.com/help/us/mail/defer/defer-
06.html/
@40000000466e85af2e8bb3ec status: local 0/10 remote 1/255
@40000000466e85b000c37904 delivery 13: deferral:
Connected_to_66.196.97.250_but_greeting_failed./Remote_host_said:_421_Message_from_(
58.65.151.33
)_temporarily_deferred_-_4.16.50._Please_refer_to_http://help.yahoo.com/help/us/mail/defer/defer-
06.html/
@40000000466e85b000c57ca4 status: local 0/10 remote 0/255

Kindly Help me out in fixing such probelm ,,,,,
regards

Xia ....