any way to stop REDIRECT_ env prefix?

[Tyler MacDonald]

I'm writing a handler whose goal is to set an environment variable, then
issue an internal redirect to another page;

  $r->subprocess_env("FOO", "bar");
  $r->internal_redirect("/somewhere/else");

The problem is that when the redirected page loads, my "FOO" environment
variable has become "REDIRECT_FOO".

Is there any clean way to do this? I've also tried internal_fast_redirect
(even though the docs seem to say it's naughty) with the same results.

        Thanks,
                Tyler