When I use my OpenID, http://thewordnerd.info, I am redirected to
http://thewordnerd.myopenid.com, the identity to which thewordnerd.info
delegates. That is, I'm redirected to the exact identity URL, not to an
authorization link.

I am successfully using thewordnerd.info as my identity on many sites, so I
know the delegation is pretty standard. It's stock WordPress with the
delegation plugin. I also just attempted registration on http://identi.ca
and successfully exchanged sreg data. So it seems like something is broken
when using a delegate specifically with ikiwiki, and while I can use
thewordnerd.myopenid.com, I'd rather use my delegate and free myself to
switch to other providers in the future.

> Hmm, I entered http://thewordnerd.info as the openid, and ended up at
> http://thewordnerd.myopenid.com/ , which seems right? --[[Joey]]

Sorry, didn't notice this edit. But, no, that is incorrect. Entering http://thewordnerd.info or thewordnerd.info should do the exact same thing that entering http://thewordnerd.myopenid.com does--in your case, prompt you to log in, in mine, ask if I want to verify the request. It's redirecting to the page itself, not using it as an OpenID provider.

Unfortunately I don't speak or understand enough Perl to fix this, nor do I understand how to use its debugger, but it looks as if the consumer should support delegation. Not sure why it's behaving incorrectly here.