Unknown directive "set" in .../nginx.conf

Hello,

I’m trying to configure nginx to be working with memcached, as shown
here:
http://wiki.codemongers.com/NginxHttpMemcachedModule

my server config looks like this:



location / {
set $memcached_key $uri;
memcached_pass localhost:11511;
default_type text/html;
error_page 404 = /fallback;
}

and it fails with:
unknown directive “set” in …/nginx.conf

Eugene.