Wiki tags and categories links do not work

Hi,

I've set up a bare-bones wiki at http://drawingwithnumbers.artisart.org/wiki/jonathans-tableau-notes/

I've set up some tags, however when I go to an active one like:

http://drawingwithnumbers.artisart.org/wiki/tags/general/

I get a 404 error.

I'm using the Twenty Twelve theme, with permalinks set to the post name. I've tried resetting the permalinks to the post number, but that didn't change anything. Any suggestions?

Jonathan