I noticed this issue with both, Pure v1 and Pure V2
Java SCRIPT
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var response = {"message":null,"list":null,"validation":{"subject":"you must specify a subject"}}
$("#PostIdea").autoRender(response.validation);
HTML
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<form action="/Idea/Post" id="PostIdea" method="post">
<fieldset>
<legend>Fields</legend>
<p>
<label for="subject">subject:</label>
<input id="subject" name="subject" type="text" value="" />
<span class="subject">validatin message</span>
</p>
<p>
<label for="contents">contents:</label>
<textarea cols="20" id="contents" name="contents" rows="2" style="width:500px; height:250px"> </textarea>
<span class="contents">validatin message</span>
</p>
<p>
<label for="contents">Tags:</label>
<input id="tags" name="tags" type="text" value="" />
</p>
<p>
</p>
</fieldset>
</form>