diff --git a/lib/ace/layer/cursor.js b/lib/ace/layer/cursor.js
index a796c84a..9456be27 100644
--- a/lib/ace/layer/cursor.js
+++ b/lib/ace/layer/cursor.js
@@ -130,7 +130,7 @@ var Cursor = function(parentEl) {
             this.element.appendChild(this.cursor);
         }
         
-        if (overwrite) {
+        if (this.overwrite) {
             dom.addCssClass(this.cursor, "ace_overwrite");
         } else {
             dom.removeCssClass(this.cursor, "ace_overwrite");