Gzip in web.config not working for me

Question

I am having problems setting up gzip on an IIS7 server via the web.config. The following is the setup

<httpCompression minFileSizeForComp="0" doDiskSpaceLimiting="false"
          staticCompressionDisableCpuUsage="98" staticCompressionEnableCpuUsage="95"
          dynamicCompressionEnableCpuUsage="30" dynamicCompressionDisableCpuUsage="60"
          directory="%SystemDrive%\inetpub\temp\IIS Temporary Compressed Files">
        <scheme name="gzip" dll="%Windir%\system32\inetsrv\gzip.dll" />
        <staticTypes>
            <clear />
            <add mimeType="*/*" enabled="true" />
        </staticTypes>
        <dynamicTypes>
            <clear />
            <add mimeType="*/*" enabled="true" />
        </dynamicTypes>
    </httpCompression>

Looking at the yslow plugin in firefox, css files, javascript files arent getting gzipped. Any ideas where I am going wrong? I presume I have the config incorrect.