--- C:/igmp_patch/igmp_original.c	Fri Nov 16 14:31:11 2007
+++ C:/igmp_patch/igmp.c	Fri Mar 07 13:42:28 2008
@@ -350,7 +350,7 @@
 
   /* Note that the length CAN be greater than 8 but only 8 are used - All are included in the checksum */    
   iphdr = p->payload;
-  if (pbuf_header(p, -(IPH_HL(iphdr) * 4)) || (p->len < IGMP_MINLEN)) {
+  if (pbuf_header(p, -(s16_t)(IPH_HL(iphdr) * 4)) || (p->len < IGMP_MINLEN)) {
     pbuf_free(p);
     IGMP_STATS_INC(igmp.lenerr);
     LWIP_DEBUGF(IGMP_DEBUG, ("igmp_input: length error\n"));
@@ -718,19 +718,17 @@
 
   iphdr = p->payload;
   if (dest != IP_HDRINCL) {
-    iphdr->_ttl_proto = (proto<<8);
-    iphdr->_ttl_proto |= ttl;
+    iphdr->_ttl_proto = htons((ttl<<8) | proto);
 
     /*  iphdr->dest = dest->addr; */
     ip_addr_set(&(iphdr->dest), dest);
 #ifdef HAVE_BITFIELDS
-    iphdr->_v_hl_tos |= ((IP_HLEN+ ROUTER_ALERTLEN)/4)<<16;
-    iphdr->_v_hl_tos |= 4<<24;
+    iphdr->_v_hl_tos |= ((IP_HLEN+ ROUTER_ALERTLEN)/4)<<16;  ??? htons, _v_hl_tos is u16_t ???
+    iphdr->_v_hl_tos |= 4<<24;                               ??? htons, _v_hl_tos is u16_t ???
 #else
-    iphdr->_v_hl_tos = (4 << 4) | ((IP_HLEN + ROUTER_ALERTLEN)/ 4 & 0xf);
+    iphdr->_v_hl_tos = htons( ((0x4000 | (((IP_HLEN+ROUTER_ALERTLEN)/ 4) & 0xf) << 8) | 0) );
 #endif /* HAVE_BITFIELDS */
 
-    iphdr->_v_hl_tos |= 0;
     iphdr->_len       = htons(p->tot_len);
     iphdr->_offset    = htons(0);
     iphdr->_id        = htons(ip_id++);
@@ -742,7 +740,7 @@
     }
 
     iphdr->_chksum = 0;
-    iphdr->_chksum = inet_chksum(iphdr, IP_HLEN + ROUTER_ALERTLEN);
+    iphdr->_chksum = htons(inet_chksum(iphdr, IP_HLEN + ROUTER_ALERTLEN));
   } else {
     dest = &(iphdr->dest);
   }