diff --git a/README b/README
index 19cf790c63..c624c76613 100644
--- a/README
+++ b/README
@@ -134,6 +134,7 @@ Building
 		Slackware Linux 7.0.1 with glibc 2.1.3
 		OpenBSD 2.6, 2.8, -current
 		UnixWare 7.1.1
+		HP-UX 10.20
 
 	To build, just