Bug #362 is fixed now.
diff --git a/ospfd/ospf_interface.c b/ospfd/ospf_interface.c
index bf53668..862735b 100644
--- a/ospfd/ospf_interface.c
+++ b/ospfd/ospf_interface.c
@@ -781,6 +781,11 @@
     OSPF_ISM_EVENT_SCHEDULE (oi, ISM_LoopInd);
   else
     {
+      struct ospf *ospf = ospf_lookup ();
+      if (ospf != NULL)
+        ospf_adjust_sndbuflen (ospf, oi->ifp->mtu);
+      else
+        zlog_warn ("%s: ospf_lookup() returned NULL");
       ospf_if_stream_set (oi);
       OSPF_ISM_EVENT_SCHEDULE (oi, ISM_InterfaceUp);
     }