private boolean isAllowedAsForeignMarkup(String tagname, CleanTimeValues cleanTimeValues){
    	if (!properties.isNamespacesAware()) return false;
    	if (tagname.contains(":")) return true;
    	if (cleanTimeValues.namespace == null || cleanTimeValues.namespace.size() == 0) return false;
    	String ns = cleanTimeValues.namespace.peek();
    	if (ns == null) return false;
    	if (ns.equals("http://www.w3.org/1999/xhtml")) return false;
    	return true;
    }