Here's a shot:

#!/usr/bin/perl -n
$s{$&}++while/\w{4,}/g}{print map"$s{$_}\t$_\n"x($s{$_}>1),keys%s
[download]

_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker, who'd like a (from-home) job
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;