diff --git a/lib/ChangeLog b/lib/ChangeLog
index 00b11a1..86a3b85 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,9 @@
+2005-04-08 Andrew J. Schorr <ajschorr@alumni.princeton.edu>
+
+	* zebra.h: If GNU_LINUX is defined, then define _GNU_SOURCE.  This
+	  fixes a problem where we were not getting the declaration of strnlen
+	  in <string.h>.
+
 2005-04-08 Hasso Tepper <hasso at quagga.net>
 
 	* routemap.[ch]: Added "description ..." command.
diff --git a/lib/zebra.h b/lib/zebra.h
index 7d907ed..3a93b7a 100644
--- a/lib/zebra.h
+++ b/lib/zebra.h
@@ -25,6 +25,10 @@
 #include "config.h"
 #endif /* HAVE_CONFIG_H */
 
+#ifdef GNU_LINUX
+#define _GNU_SOURCE
+#endif /* GNU_LINUX */
+
 #ifdef SUNOS_5
 #define _XPG4_2
 #define __EXTENSIONS__