This is really ugly (maybe someone could improve it with pack/unpack), but it reproduces your desired output:

#!perl

use strict;
use warnings;

my @un_sorted = (
   [3, 4, 23, 4, 5],
   [3, 4, 56, 2, 4],
   [2, 3, 43, 5, 3],
   [2, 3, 43, 6],
   [3, 4]
);
my $end = chr(1e6);

print join "\n",
   map { join ',', @$_ }
   map { splice @$_, $#_; $_ }
   map { [(map(ord, split('', $_)))]}
   sort 
   map { join('', map chr, @$_) . $end }
   @un_sorted;
[download]

It's a GRT (kinda, probably not the best performance, though). The trick with the end marker is especially ugly, but without it the output would be wrong.
Hope this helped.
CombatSquirrel.