diff --git a/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c b/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c
index 8065a6b61..3c58e266a 100644
--- a/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c
+++ b/demos/ARM7-AT91SAM7X-LWIP-GCC/lwip/lwipthread.c
@@ -264,7 +264,7 @@ msg_t lwip_thread(void *p) {
   evtStart(&evt);
   chEvtRegisterMask(&evt.et_es, &el0, PERIODIC_TIMER_ID);
   chEvtRegisterMask(macGetReceiveEventSource(&ETH1), &el1, FRAME_RECEIVED_ID);
-  chEvtPend(PERIODIC_TIMER_ID | FRAME_RECEIVED_ID);
+  chEvtAddFlags(PERIODIC_TIMER_ID | FRAME_RECEIVED_ID);
 
   /* Goes to the final priority after initialization.*/
   chThdSetPriority(LWIP_THREAD_PRIORITY);