diff --git a/src/include/lwip/tcpip.h b/src/include/lwip/tcpip.h
index ef13c167..b112767c 100644
--- a/src/include/lwip/tcpip.h
+++ b/src/include/lwip/tcpip.h
@@ -109,11 +109,11 @@ enum tcpip_msg_type {
 #if LWIP_NETIF_API
   TCPIP_MSG_NETIFAPI,
 #endif /* LWIP_NETIF_API */
-  TCPIP_MSG_CALLBACK,
 #if LWIP_TCPIP_TIMEOUT
   TCPIP_MSG_TIMEOUT,
   TCPIP_MSG_UNTIMEOUT,
 #endif /* LWIP_TCPIP_TIMEOUT */
+  TCPIP_MSG_CALLBACK
 };
 
 struct tcpip_msg {