Should the error log be set to INFO on a sever side level, or the virtual site level? I have it set to INFO on the virtual site level, but it doesn't log any error.
Also, I have several custom error pages defined, including the 404 error. Can it affect somehow the error log? Worth to say, that this site worked well on Apache2, but I have achieved the custom error pages effect there via the .htaccess file, and here I had to define them in the control panel.