文件下载时奇怪的403错误

Apache2服务器默认编码为gb2312
tomcat5.5默认编码为GBK
下载文件名中带有中文的文件时直接保存没有问题，但使用超级旋风或flashget之类的断点续传软件会报403禁止访问错误。
一下是使用超级旋风时线程1的信息：

2007-06-05   14:52:40   172.18.42.149
2007-06-05   14:52:40   GET   /upload/updatefile/eterm/1.0.0.2/eTerm%D7%D4%D6%FA%C5%E0%D1%B5%A3%A80.3%B0%E6%A3%A9.chm   HTTP/1.1
2007-06-05   14:52:40   Accept:   */*
2007-06-05   14:52:40   Cache-Control:   no-cache
2007-06-05   14:52:40   Connection:   close
2007-06-05   14:52:40   Cookie:   JSESSIONID=B0B4A0B006E902BCCDD44339D9D14EDE
2007-06-05   14:52:40   Host:   172.18.42.149
2007-06-05   14:52:40   Pragma:   no-cache
2007-06-05   14:52:40   Range:   bytes=0-
2007-06-05   14:52:40   Referer:   http://172.18.42.149:8080/upload/admin_login.jsp
2007-06-05   14:52:40   User-Agent:   Mozilla/5.0   (compatible;   MSIE   6.0;   Windows   NT   5.0)
2007-06-05   14:52:40   HTTP/1.1   403   Forbidden
2007-06-05   14:52:40   Date:   Tue,   05   Jun   2007   06:52:40   GMT
2007-06-05   14:52:40   Server:   Apache/2.0.55   (Win32)   mod_jk/1.2.15
2007-06-05   14:52:40   Content-Length:   352
2007-06-05   14:52:40   Connection:   close
2007-06-05   14:52:40   Content-Type:   text/html;   charset=iso-8859-1
2007-06-05   14:52:40   GET   /upload/updatefile/eterm/1.0.0.2/eTerm%D7%D4%D6%FA%C5%E0%D1%B5%A3%A80.3%B0%E6%A3%A9.chm   HTTP/1.1
2007-06-05   14:52:40   Accept:   */*
2007-06-05   14:52:40   Cache-Control:   no-cache
2007-06-05   14:52:40   Connection:   close

请各位大大帮小弟答疑解惑，谢谢

你下载功能是用什么实现的

直接连接文件进行下载如http://xx.xxx.xx.xxx/xxx/xx.x

关注一下。