rem: return Element.classNames(element).add(className); 
add: Element.classNames(element).add(className); return element; 
context:   addClassName: function(element, className) {    if (!(element = $(element))) return;    return Element.classNames(element).add(className);  },
meta: 1164	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/1164/cb2408a82c9bc93bef177dc33a8981bc36800839/prototype.js/buggy/tools/prototype.js