rem: this.registerCallback(this.element); 
add: this.registerCallback(this.element, this.trigger); 
context:   initialize: function(element, callback) {    this.element  = $(element);    this.callback = callback;    this.lastValue = this.getValue();    if (this.element.tagName.toLowerCase() == 'form')      this.registerFormCallbacks();    else      this.registerCallback(this.element);  },
meta: 1410	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1410/e3bfd08cbcbffddf53de4f0f6030a794402cf532/prototype.js/buggy/railties/html/javascripts/prototype.js