rem: var field = document.getElementById("mailnewsStartPageUrl"); field.disabled = !checked; 
add: document.getElementById("mailnewsStartPageUrl").disabled = !checked; 
context: function StartPageCheck(){  var checked = document.getElementById("mailnewsStartPageEnabled").checked;  var field = document.getElementById("mailnewsStartPageUrl");  field.disabled = !checked;}
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/3676d111d5e80b47a8353b93d57626115bcddac2/pref-mailnews.js/buggy/mailnews/base/prefs/resources/content/pref-mailnews.js