i wrote on configuration file

location /empty {
empty_gif;
expire 0;
}


and.... http://www.mydomain.com/empty

not 1x1 pixel gif. just 404 not found

location /_.gif {
empty_gif;
expire 0;
}

and too!

http://www.mydomain.com/_.gif

also 404 not found.

how can i use empty gif module?

OS : Ubuntu 10.04
Installed by apt-get