Support for oointerface

I got an error 
trying to process an oointerface element using the 1.70.1 XHTML style sheets and 
Docbook 4.4. The error is:

Element oointerface 
in namespace ' ' encountered in para, but no template 
matches.

 

Is this a know bug? 
Or should it be added to the sourceforge bug 
tracker?