I normally am authenticated in my blog, whenever I’m using my own browser, so, I took a while to notice that anyone trying to access my blog was getting “500 Internal Server Error”.

Apparently it was the plugin “WP Super Cache” for WordPress which was causing the problem (I, has authenticated user, was not because the plugin was not caching anything for me, I think…). Disabling it and clearing the cache solved the problem…

Oh well…