请那位高手帮忙看看，为何发到国外的信经常出现以下错误，谢谢！

lph180

12:12 00:58 SMTP-(0A0C00A4) >MAIL FROM:<pr.zhou@XXXX.com><br>
12:12 00:58 SMTP-(0A0C00A4) 250 Ok<br>
12:12 00:58 SMTP-(0A0C00A4) >RCPT To:<XXXXX@XXXXXXXX.com><br>
12:12 00:58 SMTP-(0B200228) 354 End data with <CR><LF>.<CR><LF><br>
12:12 00:58 SMTP-(0A0C00A4) 250 Ok<br>
12:12 00:58 SMTP-(0A0C00A4) >DATA<br>
12:12 00:58 SMTP-(0A0C00A4) 354 End data with <CR><LF>.<CR><LF><br>
12:12 00:59 SMTPD(0FD400DE) [202.101.6.97] connect 202.101.6.97 port 3452<br>
12:12 00:59 SMTP-(0A0C00A4) >.<br>
12:12 00:59 SMTP-(0A0C00A4) rl-recv: connection aborted<br>
12:12 00:59 SMTP-(0A0C00A4) <br>
12:12 00:59 SMTP-(0A0C00A4) SMTP_DELIV_FAILED<br>
12:12 00:59 SMTP-(0A0C00A4) >QUIT<br>
12:12 00:59 SMTP-(0A0C00A4) rl-recv: connection aborted