diff --git a/configure.ac b/configure.ac
index e99a1292d6..18c0ad4164 100644
--- a/configure.ac
+++ b/configure.ac
@@ -234,6 +234,7 @@ GTK_CFLAGS=$GTK2_CFLAGS
 GTK_LIBS=$GTK2_LIBS
 AC_SUBST(GTK_LIBS)
 AC_SUBST(GTK_CFLAGS)
+AC_SUBST(HAVE_GTK)
 
 
 dnl Check for X11 extensions