I've found a more portable way to abuse sort: use a sort function that does result in a defined order, but obfuscate it. For a (quite rudamentary) example, see my new signature:

{my$c;$ x=sub{++$c}}map{$ \.=$_->()}map{my$a=$_->[1];
sub{$a++ }}sort{_($a->[0 ])<=>_( $b->[0])}map{my@x=(&
$x( ),$ _) ;\ @x} split //, "rPcr t lhuJnhea eretk.as
o";print;sub _{ord(shift)*($=-++$^H)%(42-ord("\r"))};
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Of coures, for serious obfuscation something much more obscure than modular arithmetic would be called for in the sort function, but this is just a JAPH.