加密WCF消息密码

负责开发基于Java的web服务的第三方反馈给我们，要求消息头需要看起来像这样:

<soapenv:Header>
 <wsse:Security>
     <xenc:ReferenceList>
        <xenc:DataReference URI="#EncDataId-1"/>
     </xenc:ReferenceList>
     <wsse:UsernameToken>
        <wsse:Username>[snip]</wsse:Username>
        <xenc:EncryptedData Id="EncDataId-1" Type="http://www.w3.org/2001/04/xmlenc#Element">
           <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes256-cbc"/>
           <ds:KeyInfo xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
              <ds:KeyName>[snip]</ds:KeyName>
           </ds:KeyInfo>
           <xenc:CipherData>
              <xenc:CipherValue>[snip]</xenc:CipherValue>
           </xenc:CipherData>
        </xenc:EncryptedData>
     </wsse:UsernameToken>
  </wsse:Security>
</soapenv:Header>

鉴于我对这种安全巫术的非常肤浅的理解，我很难弄清楚如何配置我的客户端来产生这样的头。现在我的代码看起来像这样:

client.ClientCredentials.UserName.UserName = "[snip]";
client.ClientCredentials.UserName.Password = "[snip]";

和header:

<s:Header>
    <o:Security s:mustUnderstand="1" xmlns:o="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd">
        <o:UsernameToken u:Id="uuid-e906a1ca-aa63-474c-b4ac-cf9b90ab2435-1">
            <o:Username>[snip]</o:Username>
            <o:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">[snip]</o:Password>
        </o:UsernameToken>
    </o:Security>
</s:Header>

和绑定:

<binding name="SMSSoap11">
    <security mode="TransportWithMessageCredential" />
</binding>