Under 5.004_04, I was able to strip this down even further and get the same output from the untie.

#!/bin/perl -w
use strict;

package Tied;

sub TIESCALAR
{
        my $class = shift;
        my $o = shift;
        bless \$o, $class;
}

sub FETCH
{
        my $self = shift;
        print "<fetch>\n";
        $self;
}

sub foo {"TiedFoo\n";}

package main;

my $o;
tie $o, 'Tied';
print $o->foo();

untie $o;
eval { print $o->foo() };
print "NoFoo\n" if $@;
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In the end, $o was still tied.

yours,
Herveus