diff --git a/drivers/net/mmnif.c b/drivers/net/mmnif.c
index 616652cc..297bcec4 100644
--- a/drivers/net/mmnif.c
+++ b/drivers/net/mmnif.c
@@ -23,7 +23,7 @@
 #include <lwip/ip.h>		/* struct iphdr*/
 #include <lwip/tcpip.h>		/* tcpip_input()*/
 
-//#define DEBUG_MMNIF
+#define DEBUG_MMNIF
 
 #ifdef DEBUG_MMNIF
 #include "util.h"			/* hex dump */