diff --git a/examples/ipv6/rpl-udp/Makefile b/examples/ipv6/rpl-udp/Makefile
index 77d33d7f4..270ccff11 100644
--- a/examples/ipv6/rpl-udp/Makefile
+++ b/examples/ipv6/rpl-udp/Makefile
@@ -6,4 +6,11 @@ WITH_UIP6=1
 UIP_CONF_IPV6=1
 CFLAGS+= -DUIP_CONF_IPV6_RPL
 
+ifdef SERVER_REPLY
+CFLAGS+=-DSERVER_REPLY=$(SERVER_REPLY)
+endif
+ifdef PERIOD
+CFLAGS+=-DPERIOD=$(PERIOD)
+endif
+
 include $(CONTIKI)/Makefile.include
diff --git a/examples/ipv6/rpl-udp/udp-client.c b/examples/ipv6/rpl-udp/udp-client.c
index e5b27f832..2490399bb 100644
--- a/examples/ipv6/rpl-udp/udp-client.c
+++ b/examples/ipv6/rpl-udp/udp-client.c
@@ -46,8 +46,12 @@
 #define DEBUG DEBUG_PRINT
 #include "net/uip-debug.h"
 
+#ifndef PERIOD
+#define PERIOD 60
+#endif
+
 #define START_INTERVAL		(15 * CLOCK_SECOND)
-#define SEND_INTERVAL		(60 * CLOCK_SECOND)
+#define SEND_INTERVAL		(PERIOD * CLOCK_SECOND)
 #define SEND_TIME		(random_rand() % (SEND_INTERVAL))
 #define MAX_PAYLOAD_LEN		30
 
diff --git a/examples/ipv6/rpl-udp/udp-server.c b/examples/ipv6/rpl-udp/udp-server.c
index 2ce2a046d..cbafb0da3 100644
--- a/examples/ipv6/rpl-udp/udp-server.c
+++ b/examples/ipv6/rpl-udp/udp-server.c
@@ -68,6 +68,7 @@ tcpip_handler(void)
            UIP_IP_BUF->srcipaddr.u8[sizeof(UIP_IP_BUF->srcipaddr.u8) - 1]);
     PRINTF("\n");
 #if SERVER_REPLY
+    PRINTF("DATA sending reply\n");
     uip_ipaddr_copy(&server_conn->ripaddr, &UIP_IP_BUF->srcipaddr);
     uip_udp_packet_send(server_conn, "Reply", sizeof("Reply"));
     uip_create_unspecified(&server_conn->ripaddr);