-#if defined(__WXMSW__)
-#include "wx/msw/dde.h"
-#elif defined(__WXMOTIF__)
-#include "wx/motif/dde.h"
-#elif defined(__WXGTK__)
-#include "wx/gtk/dde.h"
-#elif defined(__WXMAC__)
-#include "wx/mac/dde.h"
-#elif defined(__WXPM__)
-#include "wx/os2/dde.h"
+#include "wx/list.h"
+
+class WXDLLIMPEXP_FWD_BASE wxDDEClient;
+class WXDLLIMPEXP_FWD_BASE wxDDEServer;
+class WXDLLIMPEXP_FWD_BASE wxDDEConnection;
+
+WX_DECLARE_USER_EXPORTED_LIST(wxDDEClient, wxDDEClientList, WXDLLIMPEXP_BASE);
+WX_DECLARE_USER_EXPORTED_LIST(wxDDEServer, wxDDEServerList, WXDLLIMPEXP_BASE);
+WX_DECLARE_USER_EXPORTED_LIST(wxDDEConnection, wxDDEConnectionList, WXDLLIMPEXP_BASE);
+
+#if defined(__WINDOWS__)
+ #include "wx/msw/dde.h"
+#else
+ #error DDE is only supported under Windows