I have admx and adml file. In my admx file

<policy name="pname" class="Machine" displayName="$(string.pname)" explainText="$(string.pname_Help)" presentation="$(presentation.pname)" key="Software\Policies\xxx\x" valueName="v_pname">
    <parentCategory ref="zz" />
    <supportedOn ref="SUPPORTED_ProductOnly" />
    <enabledValue>
        <decimal value="1" />
    </enabledValue>
    <disabledValue>
        <decimal value="0" />
    </disabledValue>
    <elements>
      <multitext id="pname_MultiText" valueName="h_pname" defaultValue="$(string.pname_multi_default)" maxStrings="50" maxLength="10240">
      </multitext>
    </elements>
</policy>

In my adml,

<stringTable>
<string id="pname">
Policy Name
</string>
<string id="pname_help">
Policy help text
</string>
<string id="pname_multi_default">
Default value
</string>
</stringTable>
<presentation id="pname">
  <listBox refId="pname_MultiText"> multitext:  </listBox>
</presentation>

I don't find any documentation on how we can have default value in the multiTextBox. I see default values for textBox elements but no documentation on multiText. Is it even possible to have default values for multiTextBox?