diff --git a/lib/imap.js b/lib/imap.js
index b6de90d..9850c46 100644
--- a/lib/imap.js
+++ b/lib/imap.js
@@ -954,7 +954,7 @@ ImapConnection.prototype.addKeywords = function(uids, flags, cb) {
 };
 
 ImapConnection.prototype._addKeywords = function(which, uids, flags, cb) {
-  if (!this._state.box._newKeywords)
+  if (!this._state.box.newKeywords)
     throw new Error('This mailbox does not allow new keywords to be added');
   this._store(which, uids, flags, true, cb);
 };
@@ -1129,7 +1129,7 @@ ImapConnection.prototype._serverSupports = function(capability) {
 };
 
 ImapConnection.prototype._store = function(which, uids, flags, isAdding, cb) {
-  var isKeywords = (arguments.callee.caller === this.addKeywords
+  var isKeywords = (arguments.callee.caller === this._addKeywords
                     || arguments.callee.caller === this.delKeywords);
   if (this._state.status !== STATES.BOXSELECTED)
     throw new Error('No mailbox is currently selected');