add: setEnabled(setDefaultButton, false); 
context: function onSetDefault(event) {  if (event.target.getAttribute("disabled") == "true") return;  var result = getServerIdAndPageIdFromTree(accounttree);  if (!result) return;  var account = getAccountFromServerId(result.serverId);  if (!account) return;  accountManager.defaultAccount = account;}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/7bd4a60ebc5057ef43ad1c3b8f7faa4a1eabad93/AccountManager.js/buggy/mailnews/base/prefs/resources/content/AccountManager.js