You could use a hash that maps the month name to a number and then use a regex to change the date string.

Example: 
#!/usr/bin/perl

use strict;
use warnings;

my %mon2num = (
    Sept => 9,
    Oct  => 10,
    Nov  => 11,
    # etc
);

while (<DATA>) {
    chomp;
    my ($date, $file_name) = split(/,/);
    $date =~ s/(\S+)\s(\S+)\s(\S+)/$2 $mon2num{$1} $3/;
    print "$date\n";
}


__DATA__
Oct 31 08:30,file1
Nov 25 17:30,file2
Sept 09 12:00,file3

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In reply to Re: Convert date into day and month by fishmonger
in thread Convert date into day and month by Ma

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