--- configure.ac.orig	2014-02-08 17:40:58.405972379 +0100
+++ configure.ac	2014-02-08 17:43:32.734512294 +0100
@@ -39,6 +39,8 @@
 AC_SUBST(GTK_CFLAGS)
 AC_SUBST(GTK_LIBS)
 
+AC_CHECK_LIB(X11, XDisplayKeycodes, [], [AC_ERROR(X11 library not installed or invalid!)])
+
 # Only use GtkStatusIcon if we have it and want it
 AC_ARG_WITH(gtkstatusicon,
             AC_HELP_STRING([--without-gtkstatusicon],