Index: firmware/App/Services/MsgQueues.h
===================================================================
diff -u -r9a9d04b84f4345fca87fb14d26f09d497b08aae8 -r6c60d0d0300828750c76f2e397d4e7ccaa84bbb2
--- firmware/App/Services/MsgQueues.h	(.../MsgQueues.h)	(revision 9a9d04b84f4345fca87fb14d26f09d497b08aae8)
+++ firmware/App/Services/MsgQueues.h	(.../MsgQueues.h)	(revision 6c60d0d0300828750c76f2e397d4e7ccaa84bbb2)
@@ -32,7 +32,7 @@
 #pragma pack(push,1)
 typedef struct
 {
-#ifdef ACK_IMPLEMENTED
+#ifndef ACK_NOT_IMPLEMENTED
     S16 seqNo;                                  // sequence # (and ACK required bit) of message
 #endif
     U16 msgID;                                  // ID of message