json_encode with large strings
<p>I'm returning a html response in  a json object field <code>$o-&gt;sHtml</code>.</p>

<p>The testing <code>sHtml</code> is about 13000 characters and after <code>json_encode</code> its <code>$o-&gt;sHtml = null</code>. 
Any idea why?</p>
