diff --git a/lib/_debugger.js b/lib/_debugger.js
index 553edb8d59..eb281f796e 100644
--- a/lib/_debugger.js
+++ b/lib/_debugger.js
@@ -405,7 +405,7 @@ Client.prototype.reqFrameEval = function(expression, frame, cb) {
 // reqBacktrace(cb)
 // TODO: from, to, bottom
 Client.prototype.reqBacktrace = function(cb) {
-  this.req({ command: 'backtrace', noRefs: true } , cb);
+  this.req({ command: 'backtrace', arguments: { noRefs: true } } , cb);
 };