Creating UI object in a different thread causing crash

[wxWidget]

Hi,
M trying to lauch a dialog in a different thread, but for some reasons
its crashing.
I dont understand what I am doing wrong??? Any help would be great.

Following is the thread code:

MyThread::MyThread(wxWindow* ptrParentWnd)
        : wxThread()
{
    m_count = 0;
	m_pParentWnd = ptrParentWnd;
}

void MyThread::LaunchDialog()
{
    // before doing any GUI calls we must ensure that this thread is
the only
    // one doing it!
    wxMutexGuiEnter();
	CToolTipDialog dlg(m_pParentWnd, wxID_ANY, wxString("ToolTip
Dialog"));
	dlg.ShowModal();
    wxMutexGuiLeave();
}

void MyThread::OnExit()
{
}

void *MyThread::Entry()
{
	LaunchDialog();
    return NULL;
}


And here is the way to call that thead from somewhere in the
mainthread.
	MyThread *thread = new MyThread(this);

	if ( thread->Create() != wxTHREAD_NO_ERROR )
	{
		wxLogError(wxT("Can't create thread!"));
	}

	thread->Run();