Thanks for the responses! I was also contacted off-list by Net::OAI::Harvester's maintainer and we tracked the issue down to a rogue standalone release of XML::SAX::Base. Removing that, so that the XML::SAX::Base included with XML::SAX was used instead, resolved my problems and I was then able to install Net::OAI::Harvester cleanly.
> I am not so familiar with the oai harvesting tools in Perl, so > forgive me if I am giving you incorrect information. My vague > recollection is that there are several oai harvesters for Perl. There are, but the import tool I'm using is specifically built to use Net::OAI::Harvester. > In Ubuntu, I had to install from synaptic when CPAN failed. > If I remember correctly, the command was: > # sudo apt-get install libnet-oai-harvester-perl > > It works better than cpan in managing dependencies in my experience. Although my dev laptop is Ubuntu, the servers I deploy to tend to be running Very Old Releases of Fedora, so I try to stay within CPAN despite its warts, simply for the sake of broad compatibility. The security of running installation tests is a great bonus, too, though - in this particular case, I expect that installing Ubuntu's packaged version would have gotten me a non-working installation because the rogue XML::SAX::Base would still be there, it just wouldn't have been caught during installation.