docbook v5, svg image oddity

iv class="figure-contents">
   <div class="mediaobject">
     <object type="image/svg+xml" data="/styles/pawson/graphics/junebm.svg"
	    width="637.7952755905512">
     </object>
    <div class="caption">
      <p>Plot of  best media</p>
    </div>
   </div>
</div>

Is produced by the stylesheets.
Opening up the svg directly in FF it shows perfectly.
Any suggestions why it isn't showing in the html file please?

Puzzled!

regards

-- 
Dave Pawson
XSLT XSL-FO FAQ.
http://www.dpawson.co.uk