Oh, and when using Math::BigInt, do make sure you're using one of those lower level supporting XS libraries, or it'll be damn slow — all lower level calculations being done in Pure Perl. I'm not sure if the Math::BigInt that comes with 5.8 is that smart by itself, but older versions definitely weren't.

See the Math::BigInt docs for more info. No, it doesn't look like it's gotten any smarter.