rem: return $(element).innerHTML.match(/^\s*$/); 
add: return $(element).innerHTML.blank(); 
context:   empty: function(element) {    return $(element).innerHTML.match(/^\s*$/);  },
meta: 7608	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/7608/d556a0875c83645645bd2067594241546d26d052/prototype.js/buggy/web/js/prototype.js