Well, depends on how you decide to fix it in Perl 6. The code as written will do superpositional logic, but it will only tell you if one of the numbers is less than 256. You'd have to use & instead of | to do a conjunction.

If, on the other hand, you try to keep the bitwise-OR semantics, Perl 6 will force you to pick between ~| and +|, and if you pick the obvious one, it numerifies the string and works as intended. So I think Perl 6 is improving things in this area...er, as long as you don't forget and try to use | or & for bit operations. Doubtless that will be a cultural issue for a while...