X-Accel-Redirect can't deal with un-ascii file name

Hi, all!
I have some files with un-ascii name, and I want to use X-Accel-Redirect
to control the download access. This is my nginx-conf:

server {
listen 80;
server_name update.grandes.com.cn;
access_log logs/grandes_access.log main;
location /update/download {
rewrite ^/update/download/(.+)$ /update/download.action?path=$1
last;
proxy_pass http://localhost:8080;
proxy_redirect off;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header Host $http_host;
client_max_body_size 10240m;
client_body_buffer_size 128k;

proxy_connect_timeout 90;
proxy_send_timeout 90;
proxy_read_timeout 90;

proxy_buffer_size 4k;
proxy_buffers 4 32k;
proxy_busy_buffers_size 64k;
proxy_temp_file_write_size 64k;

}
location /h3/ {
root /usr/local/data;
internal;
proxy_hide_header X-Accel-Redirect;
add_header ETag $upstream_http_etag;
}
}

And this’s the code of ‘/update/download.action’ running in tomcat
server,

    public String file() {
            response.setHeader("X-Accel-Charset", "utf-8");
            response.setHeader("X-Accel-Redirect", path);

            return NONE;
    }

When access the path
http://update.grandes.com.cn/update/download/WH2HOSIPTV/日志.txt’,
nginx server report 500 Internal Server Error. Then I see the log, the
tomcat server print the path parameter like this ‘WH2HOSIPTV/־.txt’
which is right,
but the nginx log track like this;
2011/04/07 18:12:56 [crit] 2056#5500: *1 CreateFile()
“/usr/local/data/WH2HOSIPTV/.txt” failed (1113: No mapping for the
Unicode character exists in the target multi-byte code page), client:
127.0.0.1, server: update.grandes.com.cn, request: “GET
/update/download/WH2HOSIPTV/%E6%97%A5%E5%BF%97.txt HTTP/1.1”, upstream:
http://127.0.0.1:8080/update/download.action?path=WH2HOSIPTV/日志.txt”,
host: “update.grandes.com.cn”.

I try to run nginx and tomcat server both in Red Hat Enterprise Linux AS
release 4 with environment variables LANG=zh_CN.UTF-8 and windows xp
which
charset is GBK, and try to change X-Accel-Charset to ‘GBK’, the nginx
always report 500 error. The problem existes both in nginx-0.8.54 and
nginx-0.9.6. But when I change the code in ‘/update/download.action’
like
this, it works fine! Is this a bug of nginx?

    public String file() {
            response.setHeader("X-Accel-Charset", "utf-8");
            response.setHeader("X-Accel-Redirect", new

String(path.getBytes(“utf-8”), “iso-8859-1”));

            return NONE;
    }

Best regards