Yeah, that's the problem I discussed elsewhere. Here's a simple fix:

#!/usr/bin/perl -w
 
use strict;
 
my @h = ( qw(
                psapp1
                psapp
                psapp2
                psepapp1
                psepapp
                psepapp2
                psimgprod
                pspappuat
                pswebapp2
                pswebapp
              ) );
 
my @h_sorted = @h[
        map { unpack "N", substr($_,-4) }
        sort
        map {
            my $key = $h[$_];
            $key =~ s[(\d+)][ pack "N", $1 ]ge;
            $key . pack "CNN", 0, 0, $_
        } 0..$#h
];

foreach (@h_sorted) { print "$_\n"; };
[download]

This inserts 5 nul bytes which prevents the problem. 1 nul byte is enough to fix this specific case. 4 fixes all cases except for the possibility of "x0" sorting before "x". 5 fixes all cases (provided you don't have nul bytes in your strings).