I'm using apache1.3b5 and php3.0 at sunos5.5.1

Look at the following script(say "test.phtml").
    <form method=post action=show.phtml>
        New id=<input type=text size=20 name=newid>
    </form>
    <?php
         echo "<br>Your current is $REMOTE_USER<br>";
    ?>

and in show.phtml,
     <?php echo "oldid = $REMOTE_USER<br>"; 
           echo "newid = $newid<br>";
     ?>

test.html and show.phtml is located in the same directory
protected by user-authentification.

Load test.phtml, and enter new id(say "smith").
     Newid [         ]
     Your currnet id is SMITH
(SMITH is auth-user name)

then, show.phtml prints
     oldid =
     newid = smith

$REMOTE_USER is lost at post method.