diff --git a/vncviewer/ServerDialog.cxx b/vncviewer/ServerDialog.cxx
index 9d0d157..4f21eb1 100644
--- a/vncviewer/ServerDialog.cxx
+++ b/vncviewer/ServerDialog.cxx
@@ -16,6 +16,10 @@
  * USA.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #include <FL/Fl.H>
 #include <FL/Fl_Input.H>
 #include <FL/Fl_Button.H>