Our Application has been created using the Sencha generate
Code:
sencha -sdk Downloads/COP/ext-4.1.1a generate app MYAPP CMDWS/MYAPP"
Our build-impl modified to accomodate index.jsp instead of index.html
Code:
<!-- compile the page -->
        <x-sencha-command>
            compile
                ${build.options}
                page
                    -name=page
                    -in=index.jsp
                    -out=${build.dir}/index.jsp
.......................................
        </x-sencha-command>
Our index.jsp
Code:
  <link rel="stylesheet" type="text/css" href="ext/resources/css/ext-all-gray.css" media="all">
<link rel="stylesheet" type="text/css" href="resources/css/MYAPP.css" media="all">
<link rel="stylesheet" type="text/css" href="resources/css/tabpanelcss.css" media="all">
<link rel="stylesheet" type="text/css" href="resources/css/topGrid.css" media="all">
<link rel="stylesheet" type="text/css" href="resources/css/userProfile.css" media="all">
<link rel="stylesheet" type="text/css" href="resources/css/topboilerplate.css" media="all">
<link rel="stylesheet" type="text/css" href="ext/ux/form/field/BoxSelect.css" media="all">
<link rel="stylesheet" type="text/css" href="ext/ux/css/CheckHeader.css" media="all"/>
    <link rel="stylesheet" href="resources/css/default/app.css">
    
    <!-- <x-compile> -->
        <!-- <x-bootstrap> -->
            <script src="ext/ext-dev.js"></script>
            <script src="bootstrap.js"></script>
        <!-- </x-bootstrap> -->
        
        <script type="text/javascript" src="app/all-classes.js"></script>
        <script src="app/app.js"></script>
    <!-- </x-compile> -->
When the Application is built using
Code:
"sencha app build"
Build fails with the error
Code:
[ERR]        def was null
[ERR]        failed to find meta class definition for name MYAPP.model.MYAPP.model.ReviewFeedback
[ERR]        BUILD FAILED
[ERR]        com.sencha.exceptions.BasicException
Any help in understanding the issue would be greatly appreciated.

Sencha Cmd is a bit mysterious to unravel as we dig further we are expecting more.