use strict;
use warnings;

my $proxy_on='user_pref("network.proxy.type", 1);';
my $prefs_js='C:/Documents and Settings/EdwardG/Application Data/Phoen
+ix/Profiles/default/7h4tw1oc.slt/prefs.js';

open my $p,'<',$prefs_js or die $!;
my @prefs = <$p>;
close $p;

my @prefs_minus_proxy = grep !/\Q$proxy_on\E/, @prefs;

my $proxy_was_off = ($#prefs == $#prefs_minus_proxy);

open $p,'>',$prefs_js or die $!;
print $p @prefs_minus_proxy;
print $p $proxy_on if $proxy_was_off;
close $p;    

# Internet Explorer 6
my %regHash;
use Win32::TieRegistry ( TiedHash => \%regHash ); # thanks tye!
$regHash{"CUser\\Software\\Microsoft\\Windows\\CurrentVersion\\Interne
+t Settings\\ProxyEnable"}
=[ $proxy_was_off ? "0x0001" : "0x0000", "REG_DWORD" ];

$|=1;
print "Proxy is now ", $proxy_was_off ? 'ON' : 'OFF';
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