diff --git a/ArduCopter/ArduCopter.pde b/ArduCopter/ArduCopter.pde
index 0d755c6a18..86bd6e060f 100644
--- a/ArduCopter/ArduCopter.pde
+++ b/ArduCopter/ArduCopter.pde
@@ -1,6 +1,6 @@
 /// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
 
-#define THISFIRMWARE "ArduCopter V2.2 b3"
+#define THISFIRMWARE "ArduCopter V2.2 b4"
 /*
 ArduCopter Version 2.2
 Authors:	Jason Short