有谁知道　webeasymail　中如何判断一封邮件是否已经阅读？

有谁知道　webeasymail　中如何判断一封邮件是否已经阅读？20060126091419968_14786.in　邮件的内容如下：Received: 您是非法用户，请离开！-df-; Thu, 26 Jan 2006 09:14:19 +0800
From: [email protected] <[email protected]>
To: [email protected]
Subject: fdasfdas
Date: Thu, 26 Jan 2006 09:14:19 +0800
Mime-Version: 1.0
X-MSMail-Priority: Normal
Content-Type: text/plain; charset="gb2312"
Content-Transfer-Encoding: quoted-printablefdsafdsafdasf
.