error log

[etrader]

I setup error and access logs as

access_log /logs/access/$server_name.access.log main;
error_log /logs/error/$server_name.error.log info;

access logs are created correctly for each virtual host, but for
error_log "$server_name" is not transformed to the server name, and one
error log named "$server_name.error.log" is created.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,205230,205230#msg-205230