熟悉javamail和s/mime的高手请进，如何用javamail发送如内格式的邮件？？ (200分)

这是用outlook发送的加密的邮件，按照他的说明应该是兼容s/mime 2和3，但如下的格式邮件好像又不是一个正常的邮件格式，比如说他没有mime里面的附件的开头的
----=_NextPart_000_003A_01C2B8B3.63747AF0
也没有附件的类型说明等信息。
我用javamail生成的邮件总是会有附件的开头说明一段，并且outlook也不认为这是一个加密了的邮件。请高手指教。

以下是outlook发送的邮件源代码
From: <pengyubo@21cn.com>
To: <pengyubo@21cn.com>
Subject: =?gb2312?B?1eLKx7zTw9y0+Li9vP61xNPKvP4=?=
Date: Fri, 10 Jan 2003 14:20:12 +0800
MIME-Version: 1.0
Content-Type: application/x-pkcs7-mime;
smime-type=enveloped-data;
boundary="----=_NextPart_000_003A_01C2B8B3.63747AF0";
name="smime.p7m"
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
filename="smime.p7m"
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 5.50.4920.2300
X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4920.2300
MIAGCSqGSIb3DQEHA6CAMIACAQAxggLEMIIBXgIBADCBxjCBsTESMBAGA1UEChMJVHJ1c3RBc2lh
(....后面略）
这是我用javamail发的源代码
Received: from pengyb([127.0.0.1]) by 21cn.com(AIMC 2.9.5.6)
with SMTP id jm43e22870b;
Mon, 13 Jan 2003 11:32:58 +0800
X-MaxRuleNumber-200: 135766 115
X-MatchRuleNumber-200: 75289 115
X-Action-200: ,D
Received: from pengyb([218.104.154.19]) by 21cn.com(AIMC 2.9.5.6)
with SMTP id jm103e228a8c;
Mon, 13 Jan 2003 11:32:58 +0800
Message-ID: <15734641.1042428067171.JavaMail.Administrator@pengyb>
From: pengyubo@21cn.com
To: pengyubo@21cn.com
Subject: fdsafasdfsadfsdafdsa
Mime-Version: 1.0
Content-Type: application/x-pkcs7-mime;smime-type=enveloped-data;
boundary="----=_Part_0_5660886.1042428065640";name=smime.p7m
X-AIMC-AUTH: pengyubo
X-AIMC-MAILFROM: pengyubo@21cn.com
------=_Part_0_5660886.1042428065640
Content-Type: application/octet-stream;
name=smime.p7m
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
filename=smime.p7m
MIAGCSqGSIb3DQEHA6CAMIACAQAxggLEMIIBXgIBADCBxjCBsTESMBAGA1UEChMJVHJ1c3RBc2lh
(...后面略)