ngx_http_accesskey_module error

[lhmwzy]

I follow http://wiki.codemongers.com/NginxHttpAccessKeyModule#accesskey
to install the ngx_http_accesskey_module,but get an error:

2008/10/15 22:48:56 [emerg] 31870#0: unknown directive "accesskey" in
/usr/local/nginx/conf/nginx.conf71

What's the problem?