--- a/configure.ac
+++ b/configure.ac
@@ -25,13 +25,13 @@ dnl This keeps being the first instructi
 dnl Change the 2nd argument if the version increases
 dnl 1st + 2nd argument is used for distribution package name
 AC_INIT(lcr, 1.6, andreas@eversberg.eu)
-AC_PREREQ(2.59)
+AC_PREREQ(2.60)
 AC_CONFIG_SRCDIR([main.c])
 AM_CONFIG_HEADER(config.h)
 
 # fix warnings from autoconf + automake
-AC_GNU_SOURCE
-# AC_USE_SYSTEM_EXTENSIONS
+#AC_GNU_SOURCE
+AC_USE_SYSTEM_EXTENSIONS
 AM_INIT_AUTOMAKE(lcr,1.6)