diff --git a/ChangeLog b/ChangeLog
index 376327d86..d34561d1e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2008-06-26  Cody Russell  <bratsche@gnome.org>
+
+	* configure.in: Add #define GLIB_USING_SYSTEM_PRINTF
+	to glibconfig.h, which specifies if GLib is using
+	the system printf functions for g_print*().
+	(#539999, by Tim-Philipp Müller)
+
 2008-06-24  Paolo Borelli  <pborelli@katamail.com>
 
 	Bug 539770 - migrate gstrfunc unit tests to gtest
diff --git a/configure.in b/configure.in
index 70ac4db83..5fdac89fd 100644
--- a/configure.in
+++ b/configure.in
@@ -2617,6 +2617,14 @@ _______EOF
 	if test x$glib_sys_poll_h = xyes; then
 	  echo '#define GLIB_HAVE_SYS_POLL_H' >> $outfile
 	fi
+	if test x$enable_included_printf != xyes; then
+          echo "
+/* Specifies that GLib's g_print*() functions wrap the
+ * system printf functions.  This is useful to know, for example,
+ * when using glibc's register_printf_function().
+ */" >> $outfile
+	  echo '#define GLIB_USING_SYSTEM_PRINTF' >> $outfile
+	fi
 
 	cat >> $outfile <<_______EOF