Hi,
I did this simple code:

package test::test;
  use Apache2::RequestRec ();
  use Apache2::RequestUtil ();
  use Apache2::SubRequest ();
  use Apache2::Filter ();
  use APR::Table ();
  use Apache2::Const -compile => qw(OK REDIRECT DECLINED);
  use constant BUFF_LEN => 1024;

sub handler    {
    my $f = shift;
    my $return_value=Apache2::Const::DECLINED;
    $f->subprocess_env("Variable" => "value");   
    return $return_value;
}

and I have configured in my httpd.conf:

PerlTransHandler +test::test

now I make a php code that read the environment variable with no problem, but in access_log file I see that write to access raw:

::1 - - [04/Jan/2010:13:05:11 +0100] "GET /test.php HTTP/1.1" 200 1791
::1 - - [04/Jan/2010:13:05:11 +0100] "GET /test.php HTTP/1.1" 200 1791

why ?

Idel