I tested the following code on Windows XP using with Perl 5.8.8

#!C:\Program Files\Perl\bin\perl.exe

use strict;
use warnings;
use Cwd qw(abs_path);

my $path = abs_path($0);
print "$path\n";

exit(1);
[download]

It printed in the expected format: D:\Portal\Types\Program\Script_types.pl

Sorry I couldn't be of more help.