[Radiant] Question about navigation behavior

[Raine Virta]

I'm using this code as navigation of my site but there's a slight flaw. 
For example, when the page is one of the children of page ruby, r:here 
won't be active. Any ideas?
<ul>
<r:navigation urls="home:/;ruby:/ruby/">
  <r:normal><li><a href="<r:url />"><r:title /></a></li></r:normal>
  <r:here><li class="here"><a class="here" href="<r:url />"><r:title 
/></a></li></r:here>
  <r:selected><li><a href="<r:url />"><r:title /></a></li></r:selected>
</r:navigation>
</ul>