diff --git a/lib/ace/edit_session.js b/lib/ace/edit_session.js
index 2c556409..146c8b19 100644
--- a/lib/ace/edit_session.js
+++ b/lib/ace/edit_session.js
@@ -754,7 +754,7 @@ var EditSession = function(text, mode) {
     * Clears all the annotations for this session. This function also triggers the `'changeAnnotation'` event.
     **/
     this.clearAnnotations = function() {
-        this.$annotations = {};
+        this.$annotations = [];
         this._emit("changeAnnotation", {});
     };