Whats UCMA 3.0 Voicexml Browser default audio format?

Currently, I am developing a ucma 3.0 vxml application. The following is some code in the VoiceXml document.

<form><record  name="msg"beep="true"maxtime="10s"  dtmfterm="true"type="audio/x-wav">
       <prompttimeout="5s">
         Record a message after the beep.
       </prompt>
       <noinput>
         I didn't hear anything, please try again.
       </noinput>
     </record>

  <block>
    <submitnext="http://SomeServer//SomePage.aspx" enctype="multipart/form-data"method="post"namelist="msg"/>
  </block>    

</form>

At SomeServer/SomePage.aspx , save the posted recording to a wav file.whats the format of the saved wav file, 8KHz/8-bit or 8KHz/16-bit or 16KHz/16-bit?

Voicexml specification 2.0 requires that all platforms must support the playing and recording audio formats specified below:

• Raw (headerless) 8kHz 8-bit mono mu-law [PCM] single channel. (G.711) -- audio/basic (from [RFC1521])
• Raw (headerless) 8kHz 8 bit mono A-law [PCM] single channel. (G.711) -- audio/x-alaw-basic
• WAV (RIFF header) 8kHz 8-bit mono mu-law [PCM] single channel. -- audio/x-wav
• WAV (RIFF header) 8kHz 8-bit mono A-law [PCM] single channel. -- audio/x-wav

I need to get 16KHz 16-bit mono pcm recording? Is this possible?(UCMA 3.0 VoiceXml application)