[
  { 'lname' => 'Krynicky', 'fname' => 'Jenda',
    'PageId' => 1,
    'Details' => {
      Header => 'blah blah',
      Footer => 'bla bla bla',
    }
  },
  ...
];

##</code><code>##

<root>
  <page cmd:foreach set:id="$_->{PageId}" opt:required>
   <field cmd:foreachkey="! /^(PageId|Details)$/">
     <cmd:insert set:_tag="$key" set:_content="$value"/>
   </field>
   <details cmd:forkey="Details">
     <cmd:insert cmd:foreachkey set:_tag="$key" set:_content="$value"/>
   </details>
  </page>
</root>