function __isNamespaceDeclaration__(attributeName) {
  // test if attributeName is 'xmlns'
  return (attributeName.indexOf('xmlns') > -1);
}
@method DOMImplementation._isNamespaceDeclaration - Return true, if attributeName is a namespace declaration
@author Jon van Noort (jon@webarcana.com.au)
@param  attributeName : string - the attribute name
@return : boolean