--- a/util-src/pposix.c	Tue Aug 31 15:14:39 2010 +0100
+++ b/util-src/pposix.c	Tue Aug 31 15:23:41 2010 +0100
@@ -559,6 +559,7 @@
 	struct utsname uname_info;
 	if(uname(&uname_info) != 0)
 	{
+		lua_pushnil(L);
 		lua_pushstring(L, strerror(errno));
 		return 2;
 	}