diff --git a/apps/ping6/ping6.c b/apps/ping6/ping6.c
index f7835a236..369c001be 100644
--- a/apps/ping6/ping6.c
+++ b/apps/ping6/ping6.c
@@ -123,9 +123,9 @@ ping6handler(process_event_t ev, process_data_t data)
     UIP_ICMP_BUF->type = ICMP6_ECHO_REQUEST;
     UIP_ICMP_BUF->icode = 0;
     /* set identifier and sequence number to 0 */
-    memset((void *)UIP_ICMP_BUF + UIP_ICMPH_LEN, 0, 4);
+    memset((uint8_t *)UIP_ICMP_BUF + UIP_ICMPH_LEN, 0, 4);
     /* put one byte of data */
-    memset((void *)UIP_ICMP_BUF + UIP_ICMPH_LEN + UIP_ICMP6_ECHO_REQUEST_LEN,
+    memset((uint8_t *)UIP_ICMP_BUF + UIP_ICMPH_LEN + UIP_ICMP6_ECHO_REQUEST_LEN,
            count, PING6_DATALEN);
 
 
diff --git a/apps/shell/shell-ping.c b/apps/shell/shell-ping.c
index f2f15adc4..5f8de1b80 100644
--- a/apps/shell/shell-ping.c
+++ b/apps/shell/shell-ping.c
@@ -30,7 +30,7 @@
  *
  * Author: Adam Dunkels <adam@sics.se>
  *
- * $Id: shell-ping.c,v 1.5 2010/10/19 18:29:03 adamdunkels Exp $
+ * $Id: shell-ping.c,v 1.6 2011/01/12 22:58:34 nifi Exp $
  */
 
 #include <string.h>
@@ -77,9 +77,9 @@ send_ping(uip_ipaddr_t *dest_addr)
   UIP_ICMP_BUF->type = ICMP6_ECHO_REQUEST;
   UIP_ICMP_BUF->icode = 0;
   /* set identifier and sequence number to 0 */
-  memset((void *)UIP_ICMP_BUF + UIP_ICMPH_LEN, 0, 4);
+  memset((uint8_t *)UIP_ICMP_BUF + UIP_ICMPH_LEN, 0, 4);
   /* put one byte of data */
-  memset((void *)UIP_ICMP_BUF + UIP_ICMPH_LEN + UIP_ICMP6_ECHO_REQUEST_LEN,
+  memset((uint8_t *)UIP_ICMP_BUF + UIP_ICMPH_LEN + UIP_ICMP6_ECHO_REQUEST_LEN,
 	 count, PING_DATALEN);
   count++;