Huh. That's odd. I never had much luck updating Bundle::CPAN either, myself, but it never forces me to. I don't have any idea why it would. Maybe check your URL list (*shrug*) using o conf from the cpan shell. Or maybe the prerequisites_policy option. I really have no idea, though. I guess you could always try updating Bundle::CPAN manually, as with the other modules, but I imagine it's more of a hassle than it's worth, since you can install modules ok now.

bbfu
Black flowers blossom
Fearless on my breath