#!/usr/bin/perl -w
use strict;

use File::Spec;

use vars qw(@ISA $VERSION);

$VERSION = '3.2501';

print "Im ok if no warnings";
__END_

If I comment out: use vars qw(@ISA $VERSION);
I get your error mesage:
Global symbol "$VERSION" requires explicit package 
name at C:\TEMP\simple.pl line 8.