我想用特定的DTMF键，结束录音，
是否可能？
代码如下，有那里不妥当的地方，望各位大虾指点。

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<?xml version="1.0" encoding="iso-8859-1"?> 
<vxml version="2.0" xml:lang="en-US" xmlns="http://www.w3.org/2001/vxml" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> 

<form id = "Voicemail"> 
  <record name="rec" beep="true" modal="false" dtmfterm="true" finalsilence="5000ms" maxtime="10s" type="audio/x-wav"> 
      <grammar mode="dtmf" root="conf"> 
 <rule id="conf" scope="public">
 <one-of>
 <item>1</item>
 <item>2</item>
 </one-of>
 </rule>
      </grammar> 

 <prompt>record now.</prompt>
 <noinput>no input anything.<reprompt/></noinput>

      <filled> 
 <log>termchar is <value expr="rec$.termchar"/></log>
 <var name="last" expr="rec$.termchar"/>
        <prompt>your message is.</prompt> 
        <prompt><audio expr="rec"/></prompt> 
 <goto next="#Voicemail"/>
      </filled> 
  </record> 

<block> 
<prompt>over</prompt> 
</block> 
</form> 

</vxml>
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