--- src/sbin/hammer/cmd_version.c	2008/11/13 02:04:27	1.1
+++ src/sbin/hammer/cmd_version.c	2008/11/13 02:23:53	1.2
@@ -133,6 +133,11 @@ hammer_cmd_set_version(char **av, int ac
 			strerror(errno));
 		exit(1);
 	}
+	if (version.head.error) {
+		fprintf(stderr, "hammer version-upgrade ioctl: %s\n",
+			strerror(version.head.error));
+		exit(1);
+	}
 	close(fd);
 }