Lists with two or more nested items containing groups (DIVs) are badly converted to XWiki syntax

Take the following wiki syntax:

* one
** two(((
three
)))
** four(((
five
)))

If you edit this with the WYSIWYG editor and switch to source you get the following valid HTML:

<ul>
  <li>
    one
    <ul>
      <li>two<div><p>three</p></div></li>
      <li>four<div><p>five</p></div></li>
    </ul>
  </li>
</ul>

converted to:

* (((
one* two(((
three
)))
* four(((
five
)))
)))

Note that the problem doesn't reproduce if there is a single nested list item with a group. And neither if the group are on top level list items.