Re: Extension manager on Mac os 10.8.5 doesn't installs CS5.5 plugins

I am using Basicdlg plugins of CS5.5 and following are the content of mxi file.Using this mxi file and basicdlg plugin create a zxp and then swatch that it is installing on MAC OS 10.4 and 10.6 for CS 5.5, but it gives the error "Extension does not contain valid signature" during installation of same ZXP on MAC OS 10.8

<?xml version="1.0" encoding="UTF-8"?>

<macromedia-extension

    name="Test"

    version="1.0.0.0"

  >

    <author name="Test" />

    <products>

        <product name="InDesign" version="7" maxversion="8.9" />

  <product familyname="InDesign" version="9" maxversion="9.9"/>

    </products>

    <description>

        <![CDATA[]]>

    </description>

  <files>

  <!-- InDesign CS5.5 -->

  <file products="InDesign" platform="mac" minVersion="7.5" maxVersion="7.9" source="BasicDialog.sdk.InDesignPlugin" destination="$indesign/Plug-Ins/Send2Proof" file-type="plugin"/>

  </files>

</macromedia-extension>

Please help.