[autoescala]

its easy , replace this:

<vb:if condition="$show['breadcrumb']">
	<li class="navbit"><a href="{vb:raw nav_url}">{vb:raw nav_title}</a></li>
<vb:else />
	<li class="navbit lastnavbit"><span>{vb:raw nav_title}</span></li>
</vb:if>

by

<vb:if condition="$show['breadcrumb']">
<div itemscope="itemscope" itemtype="http://data-vocabulary.org/Breadcrumb">
    <li class="navbit"><a href="{vb:raw nav_url}" itemprop="url"><span itemprop="title">{vb:raw nav_title}</span></a></li>
</div>
<vb:else />
<div itemscope="itemscope" itemtype="http://data-vocabulary.org/Breadcrumb">
    <li class="navbit lastnavbit"><span><span itemprop="title">{vb:raw nav_title}</span></span></li>
</div>
</vb:if>