diff --git a/src/dump.c b/src/dump.c
index d7ed774..9bd3a5f 100644
--- a/src/dump.c
+++ b/src/dump.c
@@ -132,8 +132,12 @@
 	}
             
       /* start UDP checksum */
-      for (sum = 0, i = 0; i < IN6ADDRSZ; i++)
-	sum += ((u16 *)&ip6.ip6_src)[i];
+      for (sum = 0, i = 0; i < IN6ADDRSZ; i+=2)
+	{
+	  sum += ip6.ip6_src.s6_addr[i] + (ip6.ip6_src.s6_addr[i+1] << 8) ;
+	  sum += ip6.ip6_dst.s6_addr[i] + (ip6.ip6_dst.s6_addr[i+1] << 8) ;
+	  
+	}
     }
   else
     {