Implemented WM_NOTIFYFORMAT.

diff --git a/windows/defdlg.c b/windows/defdlg.c
index 95052cb..05f234c 100644
--- a/windows/defdlg.c
+++ b/windows/defdlg.c
@@ -227,6 +227,9 @@
             PostMessageA( hwnd, WM_COMMAND, IDCANCEL,
                             (LPARAM)GetDlgItem( hwnd, IDCANCEL ) );
             return 0;
+    
+        case WM_NOTIFYFORMAT:
+	    return DefWindowProcA( hwnd, msg, wParam, lParam );
     }
     return 0;
 }