Does MailScanner configuration error?

[Michael Luk]

I use MailScanner+Sendmail+Sophos,there are some problem happened to me
now,when sending email to some domain,such as 163.com,163.net,and so on,the
reciept can't recieve it at all,and system return email to sender just like
below:
>The original message was received at Wed, 27 Aug 2003 08:22:51 +0800
>from [218.247.37.227]
>
>   ----- The following addresses had permanent fatal errors -----
><michaelluk at 163.com>
>    (reason: 550 Your message was blocked by NetEase AntiSpam+.
pQwAALr4Sz/kACaC.1(1577))
>
>   ----- Transcript of session follows -----
>.... while talking to m203.163.com.:
>>>> DATA
><<< 550 Your message was blocked by NetEase AntiSpam+. pQwAALr4Sz/kACaC.1
(1577)
>554 5.0.0 Service unavailable
>
>Reporting-MTA: dns; mail.X.com.cn
>Arrival-Date: Wed, 27 Aug 2003 08:22:51 +0800
>
>Final-Recipient: RFC822; michaelluk at 163.com
>Action: failed
>Status: 5.2.0
>Remote-MTA: DNS; m203.163.com
>Diagnostic-Code: SMTP; 550 Your message was blocked by NetEase AntiSpam+.
pQwAALr4Sz/kACaC.1(1577)
>Last-Attempt-Date: Wed, 27 Aug 2003 08:23:04 +0800

But,If I stop Mailscanner+Sophos,only starting sendmail,sending mail to all
domain,it is all ok,why it happened???
pls help me!Thanks!