nested list handling

the xhtml input:
<ol>
<li>first</li>
<li>second</li>
<li>third</li>
<ol>
<li>sub 1</li>
<li>sub 2</li>
<li>sub 3</li>
</ol>
<li>final</li>
</ol>

should generate this ezxml doc:

<paragraph>
<ol>
<li>
<paragraph>first</paragraph>
</li>
<li>
<paragraph>second</paragraph>
</li>
<li>
<paragraph>third
<ol>
<li>
<paragraph>sub 1</paragraph>
</li>
<li>
<paragraph>sub 2</paragraph>
</li>
<li>
<paragraph>sub 3</paragraph>
</li>
</ol>
</paragraph>
</li>
<li>
<paragraph>final</paragraph>
</li>
</ol>
</paragraph>