diff --git a/ChangeLog b/ChangeLog
index fafa81b..85e1b8c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2006-05-13  Bruno Haible  <bruno@clisp.org>
+
+	* config.guess: Change support for Sun C/C++ 5.9 on Linux/x86 to
+	use compiler-specific predefines other than __sun.
+
 2006-05-12  Ben Elliston  <bje@gnu.org>
 
 	* config.sub (spu): New.
diff --git a/config.guess b/config.guess
index 7149b1b..f8901bc 100755
--- a/config.guess
+++ b/config.guess
@@ -989,7 +989,7 @@ EOF
 	LIBC=gnulibc1
 	# endif
 	#else
-	#if defined(__INTEL_COMPILER) || defined(__PGI) || defined(__sun)
+	#if defined(__INTEL_COMPILER) || defined(__PGI) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
 	LIBC=gnu
 	#else
 	LIBC=gnuaout