add: if (!passwordField) return; 
context: function onSavePassword(target) {    dump("savePassword changed! (" + target.checked + ")\n");    var passwordField = document.getElementById("server.password");        if (target.checked) {        passwordField.removeAttribute("disabled");        passwordField.value = savedPassword;    }    else {        passwordField.setAttribute("disabled", "true");        savedPassword = passwordField.value;        passwordField.value = "";    }    }
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/85b3bec1d910e001e21644b6b8cac164473a6630/aw-login.js/clean/mailnews/base/prefs/resources/content/aw-login.js