Further evidence that this is a dependency problem: I just managed to successfully upgrade on Darwin with 5.10. The upgrade was successful except for this one warning thrown repeatedly during make test:

t/00-basic......ok 7/12Use of uninitialized value $owner in substituti
+on (s///) at /usr/local/lib/perl5/site_perl/5.8.7/darwin-2level/Pod/C
+overage.pm line 288.
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