Mod_fastCGI is just not somthing that can be fixed. It is old/depeciated, but have made life easier for many small sites for several years. Kloxo-MR use mod_fastcgi if you select php-fpm as php type in webserver configure. I have found it to be the best choise for my sites, and have to live with the error reports mentioned in the header. You can try out the other options like for example proxy_fcgi_event, and the error reports will stop. It requires sethandlers to work, and I got several permission issues with it so i switched back to php-fpm. I am not at all an expert on these matters, but if anybody have experience with proxy_fcgi_event I would be glad to read how to configure this in Kloxo-MR.