asp.net RewritePath重定向HTTP头Content-Location暴露真实路径

HTTP/1.1 200 OK
Content-Length: 48150
Content-Type: image/jpeg
Content-Location: http://www.mzwu.com/test.jpg
Last-Modified: Tue, 18 Dec 2012 15:01:50 GMT
Accept-Ranges: bytes
ETag: "e119ee9b30ddcd1:1c48"
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Date: Mon, 08 Sep 2014 01:29:40 GMT

HTTP/1.1 200 OK
Content-Length: 48150
Content-Type: image/jpeg
Content-Location: mzwu.com
Last-Modified: Tue, 18 Dec 2012 15:01:50 GMT
Accept-Ranges: bytes
ETag: "e119ee9b30ddcd1:1c58"
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
Date: Mon, 08 Sep 2014 01:42:50 GMT