More Threads Problems

Does CreateThread not give a unique handle to every thread that is created? In other words, wouldn''t the following code create 4 unique threads each with a unique HANDLE and push that handle onto the vector vRecvThreadPool? The reason I ask is that the cout statement following the call to push the handle onto the vector always outputs the exact same thing: 0x00000000. I''m trying to debug this program. It runs but this output just seems peculiar.

for (iThreadCount=0; iThreadCount < 4;
     iThreadCount++)
{
    hThreadHandle = CreateThread(NULL, NULL, RecvDispatch,
                        reinterpret_cast< LPVOID >(pRecv),
                        NULL, &dwThreadID);
    if (hThreadHandle = NULL)
    {
	perror("Recieve Thread Creation Problem");
	exit(1);
    }
    
    vRecvThreadPool.push_back(hThreadHandle);
    cout << hThreadHandle << endl;			
}

Another problem that is generating an actual error is my actual thread function (worker function). In that function, if I make any call to an STL object the program crashes. Are STL objects not thread safe? For now I am only running the program with a single thread and only that thread does anything with the queue in question so it shouldn''t be an issue of multiple threads mangling the memory. Example: if(vRecvThreadPool.size() == 1) { cout << "GOOD UNTIL HERE" << endl; } will genenerate a runtime error (program dies) but if(1<2) { cout << "GOOD UNTIL HERE" << endl; } will work just fine. All of my errors are isolated around STL objects I am using. Whether it''s a call to .size(), .push_back(), or whatever. Should I be using a critical section or a mutex around these no matter if I only have 1 thread or more? Thanks for any help, Webby