Index: /trunk/src/VBox/Devices/Network/lwip-new/src/core/ipv6/ip6.c
===================================================================
--- /trunk/src/VBox/Devices/Network/lwip-new/src/core/ipv6/ip6.c	(revision 50019)
+++ /trunk/src/VBox/Devices/Network/lwip-new/src/core/ipv6/ip6.c	(revision 50020)
@@ -711,7 +711,7 @@
 
       /* Offset == 0 and more_fragments == 0? */
-      if (((frag_hdr->_fragment_offset & IP6_FRAG_OFFSET_MASK) == 0) &&
-          ((frag_hdr->_fragment_offset & IP6_FRAG_MORE_FLAG) == 0)) {
-
+      if ((frag_hdr->_fragment_offset
+           & PP_HTONS(IP6_FRAG_OFFSET_MASK | IP6_FRAG_MORE_FLAG)) == 0)
+      {
         /* This is a 1-fragment packet, usually a packet that we have
          * already reassembled. Skip this header anc continue. */