SVG within file with extension .xhtml/.html

Otto Wyss <[email protected]> Fri, 05 Nov 2010 21:25:45 +0100

Newsgroups	gmane.comp.mozilla.devel.svg
Message-ID	<[email protected]>

I've tried to implement an SVG in a web page once as .xhtml once as .html in 
SeaMonkey (2.0.8). See the 2 pages here

http://www.orpatec.ch/osm/editor/editor.xhtml
http://www.orpatec.ch/osm/editor/editor.html

Does anybody know why the 2 pages are different? What do I have to change so the 
.html shows the SVG?