Fantastic diagnosis almut and Corion! Reinstalling Scalar::Util fixed the problem, stopping the "Weak references" error, and rendering CPAN operable. You made my day!

However, I remain perplexed. I don't understand why this problem occurred or how you diagnosed it.

WRT 'why', unfortunately, I don't have a logging filesystem that could show all updates, and even if I did, I don't know how do identify the update(s) that caused this problem. My differential backup shows a change in /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/auto/List/Util/Util.so on 120209, but the problem didn't surface until 12/6/9. I surmise that it didn't surface until the modified file was loaded, but I really don't know.

WRT 'how', you say "your Perl did not compile the XS component of Scalar::Util, and your search seems to confirm that for me", but 'locate' found /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/auto/List/Util/Util.so installed (although I should have used 'ls -l' to check its current status) so I didn't see any indication of Scalar::Util installation trouble other than the "Weak references" error.

In any case, thanks again monks.