A nice and lazy approach (i.e the perl approach ;) would be to use Tie::IxHash, which will keep a tied hash in order for you e.g

use Tie::IxHash;

my %th;

tie %th => "Tie::IxHash", qw/ foo bar baz quux /;
print %th, $/;
@th{qw/one three/} = qw/two four/;
print %th, $/;

__output__

foobarbazquux
foobarbazquuxonetwothreefour
[download]

And you'll see the contents of the hash have stayed nicely ordered, all thanks to Tie::IxHash.
HTH

_________
broquaint