This systems-hound (unix-ish expectations) is busted, fair and square.
I've recently had to do a bunch of perl5 work in the Win32 world (via Strawberry as it happens), including full-blown GUI support.
I ran into more stuff that broke perl than I would have ever imagined. But mostly, this is because the environment was breaking POSIX. Live and learn.
I think the primary point of my original comment was that I'd like to minimize those kinds of surprises (multi-platform abstraction) as well as minimize language surprises (i.e. sorry, this is not your flavor of perl6).
The test suite evolving around the current specification gives me hope.