Hello,
         I was able to do it by capturing WM_NCLBUTTONDOWN in WndProc
method and setting the capture property of the form to false. Following is
the code,

protected override void WndProc(ref Message m)
{
 const int WM_NCLBUTTONDOWN  = 0x00A1;
 const int HTCAPTION = 2;

 switch(m.Msg)
 {
    case WM_NCLBUTTONDOWN:
        if((int)m.WParam == HTCAPTION)
        {
            this.Capture = false;
            m.Result = new IntPtr(0);
            return;
        }
        break;
 }

 base.WndProc (ref m);
}

  Donot forget to reset the capture back to true in some other event, as
this might cause some behaviour change(not sure though).

   I hope this works for you.

Thanks
-Obaid