title: "The type javax.el.ValueExpression cannot be resolved" error when extending checkbox related jsf components
body: <p>I am creating JSF2 custom components and eclipse shows following error at the first line of the class.</p>
  
  <pre><code>The type javax.el.ValueExpression cannot be resolved. It is indirectly referenced from required .class files
  </code></pre>
  
  <p>Error only shown when my component extends checkbox related components like <code>HtmlSelectBooleanCheckbox</code> or <code>HtmlSelectManyCheckbox</code>. Other components like <code>HtmlSelectOneMenu</code> , <code>HtmlInputText</code> are ok.
  I've checked project build-path and <code>javax.faces-2.1.14.jar</code> is already added to the build-path.</p>