With a run of ./foo.pl a=123 -b 456, I get:

Running...
Perl version: 5.006001
Osname: linux
Executable name: /usr/local/bin/perl
+

zot is not tainted
zot is not tainted
123 is tainted
123 is tainted
456 is tainted
456 is tainted
[PATH] is tainted
[PATH] is tainted
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Update:

$CGI::revision = '$Id: CGI.pm,v 1.49 2001/02/04 23:08:39 lstein Exp $'
$CGI::VERSION='2.752';
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