Nope, Sir. I do run it on a 64bit server (linux), and the Perl I use on it shows the following first line when using '-v':

This is perl 5, version 16, subversion 0 (v5.16.0) built for x86_64-linux-thread-multi

Also, I think that my "-" implementation should have been within the limits of the "sort" specifications (by the way, I don't know who I should contact about it, but it is somewhat sketchy. I mean, telling us we should provide a negative, null, or positive integer is all well and good, but telling us WHAT IT MEANS (like "a null value means that both elements have the same rank", and so on) would have been a huge improvement.

Anyway, yes, it now works correctly when using <=>, so I'm guessing that, despite the version being a 64b Perl, there is indeed a problem with the huge negative numbers I got (possibly some kind of negative overflow, or merely a bug where the function doesn't expect as much data, and "loses" important parts, like the first characters (including the sign). I really don't know.