I was wrong, MiniSendComplete shouldn't be called at all by NDIS except if explicitly asked to by the miniport (in pending case).

reactos/drivers/net/ndis/ndis

diff -u -r1.46 -r1.47
--- miniport.c	13 Dec 2004 16:50:21 -0000	1.46
+++ miniport.c	13 Dec 2004 17:16:36 -0000	1.47
@@ -830,9 +830,6 @@

                     Adapter->NdisMiniportBlock.MiniportAdapterContext, (PNDIS_PACKET)WorkItemContext, 0);
 
                 NDIS_DbgPrint(MAX_TRACE, ("back from miniport's Send handler\n"));

-
-                if (NdisStatus != NDIS_STATUS_PENDING) 
-                    MiniSendComplete((NDIS_HANDLE)Adapter, (PNDIS_PACKET)WorkItemContext, NdisStatus);

               }
 
             break;