#!/usr/bin/perl
use strict;
use warnings;

my @data = <DATA>;

print "data\n";
print @data;

my @sorted = # do a little transform
    map  { join(' ', @$_)    } # join
    sort { &by_date($a, $b)  } # sort
    map  { [ split / /, $_ ] } # split
    grep { s/^A\d+ //        } # clean
    @data;

print "sorted\n";
print @sorted;

sub by_date {
    my($a_mon,$a_day,$a_year) = split m[/], $a->[1];
    my($b_mon,$b_day,$b_year) = split m[/], $b->[1];

    return ($a_year <=> $b_year or $a_mon <=> $b_mon or $a_day <=> $b_day);
}

__DATA__
A19234 hostname 06/08/07 moredata moredata
A19284 hostname 07/09/07 moredata moredata
A19384 hostname 06/06/06 moredata moredata
A19234 hostname 07/08/07 moredata moredata
A19284 hostname 07/09/07 moredata moredata
A19384 hostname 06/09/07 moredata moredata
A19234 hostname 07/06/06 moredata moredata
A19284 hostname 07/09/07 moredata moredata
A19384 hostname 06/09/07 moredata moredata