how to create telephone links in xhtml MP

I'm trying to construct a little mobile optimized web. This web list a set of results for business and I need that android interpret the telephone link.

I have watch other webs and android show an especial intem for telephone links (with a telephone green image in a grey button) but when I try it, it seems like a usual link.

I have tried with microformars (vcard) and it not works.

My code:

<ul id="search-results">
  <li class="vcard" id="i53380"><!-- pro//ginec开发者_开发技巧ologo_madrid/clinica-dam/ -->
  <p class="fn">
    <a class="url" href="/ginecologo_madrid/clinica-dam/">Name of bussiness</a>
  </p>
  <p class="adr"><span class="street-address">Street - zipcode</span> <span class="locality">Locality</span></p>
  <p class="tel">
      <a href="tel://+34 XXXXXXXXX" class="value" >+34 XXXXXXXXX</a>
  </p>

</li>   
<!-- more results -->

Any idea?

There should be no // after the :

its

tel:+34 XXXXXXXXX

and NOT tel://+34 XXXXXXXXX