So yesterday jrockway recommended XML::Liberal as a solution to my corrupted RSS feed problem.
I initially pooh-pooh'd the idea, because I wanted to use an RSS-specific package out of laziness. Then it occurred to me that maybe I could use XML::Liberal to feed *into* XML::RSS, and in the course of researching it, I discovered XML::RSS::Liberal. And installed it. (Perhaps badly, because my cpan installer just can't cope with using /opt/perl/lib, for some reason. That's a whole 'nother entry.)
Assuming I installed it correctly, though, it's not as liberal as XML::RSS, because now it's choking on feeds that worked before ("a namespace prefix should look like [a-z_][a-z0-9.\-_]*") XML::RSS::LibXML does the same thing. And that's on things that W3C validates as good feeds (del.icio.us tag feeds, for instance), so I'm not at all sure it's installed correctly.
The original corrupted feed is still choked on, and I'm not sure I'm going to struggle much to get LibXML installed right, because I don't think it'll help. It's just *that bad*... definitely going to take XML::RSS::Liberal::Commie::Pinko to parse something like that.