diff --git a/ChangeLog b/ChangeLog
index 478413460..1e8ebf727 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2004-09-25  Roland Illig  <roland.illig@gmx.de>
+
+	* autoconf.ac: #define _GNU_SOURCE to an empty value instead of 1,
+	which conflicted with src/regex.c.
+
 2004-09-24  Roland Illig  <roland.illig@gmx.de>
 
 	* HACKING (Programming tips): added a tip concerning the NULL
diff --git a/configure.ac b/configure.ac
index 244b76e4d..49892c94a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -143,7 +143,7 @@ aux*)
     AC_DEFINE(_POSIX_SOURCE)
     ;;
 linux*)
-    AC_DEFINE(_GNU_SOURCE, 1, [Define to request GNU feature set on Linux])
+    AC_DEFINE(_GNU_SOURCE,, [Define to request GNU feature set on Linux])
     ;;
 esac