发包问题，请强烈关注？

9X下的NDIS，我从应用层传数据到VXD的缓冲区中，将传来的数据组装成NDIS_PACKET后用原来的NdisSend发包，却返回一个，NDIS_STATUS_PENDING，请问这是怎么回事，
以下是我组装NDIS_PACKET的代码：
NdisAllocatePacket(&nNdisStatus,
      &(PNDIS_PACKET)pTCPH_IPacket,
      pTCPH_AEReserved->m_hPacketPool);

if( nNdisStatus != NDIS_STATUS_SUCCESS )
{
dprintf( \"TCPH_DeferNdisSend: Could Not Allocate Packet\\n\" );
return nNdisStatus;    
}

NdisAllocateBuffer(
&nNdisStatus,
&pTCPH_IBuffer,
pTCPH_AEReserved->m_hBufferPool,
pTCPH_IPacket->m_Reserved.m_IBuffer,
FilterPacket->Size
);

if( nNdisStatus != NDIS_STATUS_SUCCESS )
{
dprintf( \"TCPH_DeferNdisSend: Could Not Allocate Buffer\\n\" );
TCPH_FreePacketAndBuffers( pTCPH_IPacket );
return nNdisStatus;    
}
// Chain Our Buffer To Our Packet
NdisChainBufferAtFront(
(PNDIS_PACKET )pTCPH_IPacket,
pTCPH_IBuffer
);
pTCPH_IPacket->m_Reserved.m_pAdapterEntry = pAdapterEntry;
//
// Setup Private SendCompleteHandler
//
pTCPH_IPacket->m_Reserved.m_ISendCompleteHandler = TCPH_DeferredNdisISendCompleteHandler;

//Write Buffer to Packet
bReturn=0;
UTIL_WriteBufToPacket(pTCPH_IPacket,FilterPacket->Buffer,FilterPacket->Size,0,&bReturn);
if (FilterPacket->Size!=bReturn)
return 0xffffffff;

pNDISVXD_NdisSend(&nNdisStatus,
     pAdapterEntry->m_hNdisBindingHandle,  
pTCPH_IPacket
);

上面问题已解决，还有一个问题是，我在什么时候释放自己组装的包？