diff -up sudo-1.7.1/configure.in.envdebug sudo-1.7.1/configure.in
--- sudo-1.7.1/configure.in.envdebug	2009-05-02 21:25:56.000000000 +0200
+++ sudo-1.7.1/configure.in	2009-05-02 21:27:17.000000000 +0200
@@ -1192,7 +1192,7 @@ AC_ARG_ENABLE(env_debug,
 [  --enable-env-debug      Whether to enable environment debugging.],
 [ case "$enableval" in
     yes)	AC_MSG_RESULT(yes)
-		AC_DEFINE(ENV_DEBUG)
+		AC_DEFINE(ENV_DEBUG, [], [Environment debugging.])
 		;;
     no)		AC_MSG_RESULT(no)
 		;;