--- a/src/internet/model/ipv6-extension.cc	Thu Dec 12 21:08:27 2013 +0100
+++ b/src/internet/model/ipv6-extension.cc	Thu Dec 12 23:16:28 2013 +0100
@@ -510,6 +510,7 @@
         {
           moreFragment = true;
           currentFragmentablePartSize = maxFragmentablePartSize;
+          currentFragmentablePartSize -= currentFragmentablePartSize % 8;
         }
       else
         {
@@ -517,10 +518,8 @@
           currentFragmentablePartSize = p->GetSize () - offset;
         }
 
-      currentFragmentablePartSize -= currentFragmentablePartSize % 8;
 
       fragmentHeader.SetNextHeader (nextHeader);
-      fragmentHeader.SetLength (currentFragmentablePartSize);
       fragmentHeader.SetOffset (offset);
       fragmentHeader.SetMoreFragment (moreFragment);
       fragmentHeader.SetIdentification (identification);