rem: onError: function(aMessage) {}, 
add: onError: function(aErrNo, aMessage) { var promptService = Components.classes["@mozilla.org/embedcomp/prompt-service;1"] .getService(Components.interfaces.nsIPromptService); promptService.alert(null, 'Error', aMessage); }, 
context:         onError: function(aMessage) {},
meta: 5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5459/84ba0f6b23fb23c850f016df48e9bb34d4fcd4f7/calendarWindow.js/buggy/calendar/resources/content/calendarWindow.js