title: jQuery Chosen Dropdown validation client site doesn't work
body: <p>My model class contains of required lookup value which is a lookup-based record:</p>
  
  <pre><code>[Required]
  [DisplayName("Business Unit")]
  public string value { get; set; }
  
  [Required] //not working on client side?
  [DisplayName("Business Group")]
  public int id_businessgroup { get; set; }
  </code></pre>
  
  <p>View:</p>
  
  <pre><code>    &lt;div class="editor-label"&gt;
          @Html.LabelFor(model =&gt; model.value)
      &lt;/div&gt;
      &lt;div class="editor-field"&gt;
          @Html.EditorFor(model =&gt; model.value)
          @Html.ValidationMessageFor(model =&gt; model.value)
      &lt;/div&gt;
  
      &lt;div class="editor-label"&gt;
          @Html.LabelFor(x=&gt;x.BusinessGroup.value)
      &lt;/div&gt;
      &lt;div class="editor-field"&gt;
          @Html.DropDownListFor(x =&gt; x.id_businessgroup, new SelectList(ViewBag.BusinessGroups,"id","value"),"Please select group from list...")
          @Html.ValidationMessageFor(x =&gt; x.id_businessgroup)
      &lt;/div&gt;
  
  @section scripts{
    @Html.Partial("ScriptUseChosen")
  }
  </code></pre>
  
  <p>Controller:</p>
  
  <pre><code>public ActionResult Create()
      {
          ViewBag.BusinessGroups = DB.BusinessGroups.Where(x =&gt; x.is_active).OrderBy(x =&gt; x.value).ToList();
          return View();
      }
  </code></pre>
  
  <p>Web.config:</p>
  
  <pre><code>&lt;add key="ClientValidationEnabled" value="true" /&gt;
  &lt;add key="UnobtrusiveJavaScriptEnabled" value="true" /&gt;
  </code></pre>
  
  <p>BundleConfig.cs:</p>
  
  <pre><code>            bundles.Add(new ScriptBundle("~/bundles/jqueryval").Include(
              "~/Scripts/jquery.validate*",
              "~/Scripts/jquery.unobtrusive*"));
  </code></pre>
  
  <p>Validation for <code>value</code> is working perfectly on client side, but it's not working on the Chosen's dropdown. What could be the reason?</p>