IIS 7.5 ASP.NET-4 Gzip压缩

我似乎无法让我的ASP.NET 4应用程序启用GZIP压缩.只有 javascript文件似乎被压缩.该页面,css等不会压缩.

未压缩的CSS文件的响应头是：

Content-Type      text/css
Last-Modified     Mon,09 Aug 2010 20:10:34 GMT
Accept-Ranges     bytes
Etag               "5d71bdecfe37cb1:0"
Server    Microsoft-IIS/7.5
Date               Sat,28 Aug 2010 14:33:56 GMT
Content-Length    3364

而对于一个被压缩的Javascript文件(scriptresource.axd)：

Cache-Control      public
Content-Type       application/x-javascript
Content-Encoding gzip
Expires    Sun,28 Aug 2011 14:33:50 GMT
Last-Modified      Sat,28 Aug 2010 14:33:50 GMT
Server     Microsoft-IIS/7.5
Date                Sat,28 Aug 2010 14:33:56 GMT
Content-Length     478

在applicationHost.config中：

<httpCompression sendCacheHeaders="false" directory="%SystemDrive%\inetpub\temp\IIS Temporary Compressed Files" noCompressionForRange="true">
        <scheR_62_11845@e name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" />
        <staticTypes>
        </staticTypes>
        <dynamicTypes>
        </dynamicTypes>
    </httpCompression>

并在应用程序web.config中：

<urlCompression  doStaticCompression="true" doDynamicCompression="true" dynamicCompressionBeforeCache="true" />
<httpCompression noCompressionForRange="false" noCompressionForhttp10="false" noCompressionForProxies="false" >
  <dynamicTypes>
    <add mimeType="text/css" enabled="true" />
  </dynamicTypes>
  <staticTypes>
    <add mimeType="text/css" enabled="true" />
  </staticTypes>
</httpCompression>

有谁能告诉我什么设置我失踪了？