Problem in multithreaded chat server.

Hi,

  I have created a multithreaded chat server and it works without any
problem in debug mode but causes a access violation in a release mode built
in

sockcore.cpp in line 468 (CAsyncSocket::AttachHandle)

Here is a description of the classes and functioning of my server:

1) class CServerThread : public CWinThread

2) class CListenSocket : public CAsyncSocket

3) class CServerSocket : public CAsyncSocket

4) CListenSocket's object is used to listen on a port.

5) In the OnAccept handler, AfxBeginThread() starts the thread.

6) The problem starts in the InitInstance() where the CAsyncSocket::Attach()
is called to attach the
   socket handle to the CAsyncSocket() object which (handle) was set in
thread class in the OnAccept()
   handler.

Here is the code :

void CListenSocket::OnAccept(int nErrorCode)
{

    CAsyncSocket soc;

    Accept(soc);

    
    CServerThread* pThread =
(CServerThread*)AfxBeginThread(RUNTIME_CLASS(CServerThread),
                                                            
THREAD_PRIORITY_NORMAL,
                                                            0,
                                                            CREATE_SUSPENDED);

    pThread->SetSocket(soc.Detach());
    pThread->SetTarget(target);
    pThread->ResumeThread();
        
    CAsyncSocket::OnAccept(nErrorCode);
}

BOOL CServerThread::InitInstance()
{
    target->PostMessage(UWM_THREADSTART, 0, (LPARAM)m_nThreadID);

    sock.SetTarget(target);
    sock.threadID = m_nThreadID;
    if(socket != NULL)
    {
        sock.Attach(socket); //PROBLEM is here
    }

    return TRUE; //But the debugger points here (in release mode ,no problem
shown in debug mode)
}

Where sock is a object of CServerSocket and SOCKET socket;

Call stack is:

  Chat Server.exe!CAsyncSocket::Attach(unsigned int hSocket=3844, long
lEvent=63) Line 132 C++

  Chat Server.exe!CServerThread::InitInstance() Line 36 C++

  Chat Server.exe!_AfxThreadEntry(void * pParam=0x0013faec) Line 113 + 0x7
bytes C++

  Chat Server.exe!_callthreadstartex() Line 348 + 0x6 bytes C

  Chat Server.exe!_threadstartex(void * ptd=0x003e7b60) Line 326 + 0x5
bytes C

  kernel32.dll!7c80b50b()
  [Frames below may be incorrect and/or missing, no symbols loaded for
kernel32.dll]

  kernel32.dll!7c8399f3()

And the exception occurs at this point in sockcore.cpp

void PASCAL CAsyncSocket::AttachHandle(
    SOCKET hSocket, CAsyncSocket* pSocket, BOOL bDead)
{
    _AFX_SOCK_THREAD_STATE* pState = _afxSockThreadState;

    BOOL bEnable = AfxEnableMemoryTracking(FALSE);

    TRY
    {
        if (!bDead)
        {
            ASSERT(CAsyncSocket::LookupHandle(hSocket, bDead) == NULL);
            if (pState->m_pmapSocketHandle->IsEmpty()) //ACCESS VIOLATION OCCURS HERE
            { ...

Please help me,
Thank you.