Per http://wiki.nginx.org/NginxHttpUpstreamModule#.24upstream_cache_status, $upstream_cache_status appeared in 0.8.3.

I run 0.8.47, and have in my conf:

<snip>
log_format cache '***$time_local '
'Server : $upstream_addr '
[b]'Status: $upstream_cache_status '[/b]
'Cache-Control: $upstream_http_cache_control '
'Expires: $upstream_http_expires '
'"$request" ($status) '
'"$http_user_agent" ';
access_log /var/log/nginx/cache.log cache;
</snip>

yet my log file does not show anything for $upstream_cache_status :

/snip
***02/Aug/2010:15:09:56 -0700 Server : XX.XX.XX.XX [color=#00FF00]Status: -[/color]Cache-Control:......
/snip

Why is that 0.8.47 does not populate $upstream_cache_status ? Do i need to downgrade the binary?

Please advise, many thanks in advance.!