error_page and log_not_found in nginx 0.7.8

[Steffen Weber]

I think I'm either misunderstanding the purpose of the log_not_found 
directive or maybe there is a bug in nginx 0.7.8. In May 2008 Igor 
recommended [1] the following configuration snippet to hand off all 
requests for non-existing files to PHP:

location / {
     error_page 404 = /index.php;
}

But this creates an entry in my error_log for each request that is 
handed off to PHP. Michael Shadle then pointed me to the log_not_found 
directive, but adding "log_not_found off;" to the configuration file 
does not seem to have any effect, no matter where I put it (http, server 
or location block).

The error I get originates from src/http/modules/ngx_http_index_module.c 
and reads

2008/08/11 10:04:17 [error] 5887#0: *1 "/doc/root/artikel/index.php" is 
not found (2: No such file or directory), client: 127.0.0.1, server: 
www.example.org, request: "GET /artikel/ HTTP/1.1", host: 
"www.example.org", referrer: "http://www.example.org/"

What am I doing wrong?

I could, of course, change the error_log directive to only log critical 
events, but I fear that I would miss some (more) important errors then.

Kind regards
Steffen Weber

[1] http://article.gmane.org/gmane.comp.web.nginx.english/4739
[2] 
http://michaelshadle.com/2008/05/01/wordpress-nginx-rewrite-rules-stop-the-insanity/