diff --git a/configure.in b/configure.in
index 80b9bd5..3310fcc 100644
--- a/configure.in
+++ b/configure.in
@@ -166,7 +166,8 @@ dnl Checks for typedefs, structures, and compiler characteristics.
 AC_C_CONST
 AC_TYPE_SIZE_T
 
-PKG_CHECK_MODULES(GTK, gtk+-2.0)
+dnl will comment in gwc.c where these versions are required:
+PKG_CHECK_MODULES(GTK, [ gtk+-2.0 >= 2.16 glib-2.0 >= 2.30 ])
 
 dnl Checks for library functions.
 AC_PROG_GCC_TRADITIONAL