title: json encoding error on joomla page (RokSprocket plugin)
body: <p>So i have a RokSprocket joomla plugin where I load all the joomla articles from table, the problem is that i have around 80 articles, and on load i show only 10 of them and a button to load more. 2nd time when i click on the button new 10 articles are loaded, after that when i want to click 3rd time, i cant load them, I get an error like this:</p>
  
  <pre><code>{"status":"error",
  "message":"UNHANDLED ERROR [2] json_encode() [function.json-encode&lt;\/a&gt;]:
  Invalid UTF-8 sequence in argument \/joomla\/libraries\/rokcommon\/RokCommon
  \/Ajax.php:93","payload":null}
  </code></pre>
  
  <p>And in the line 93 of that file (Ajax.php) I have </p>
  
  <pre><code>$encoded_result = json_encode($result);
  </code></pre>
  
  <p>I don't know where is the error really, how can I load 2 times 20 articles OK, and than when i click 3rd time I get an error and nothing loaded.</p>
  
  <p>This is also shown in the Firebug console:</p>
  
  <pre><code>Error: RokSprocket Error [model: 
  mosaic, model_action: getPage, 
  params: {"moduleid":"706","behavior":"append","displayed":[382,400,401,402,403,404,405,406,407,408,409,410,411,412,413,414,415,416],"filter":"all",
  "page":3}]: 
  UNHANDLED ERROR [2] json_encode() [&lt;a href='function.json-encode'&gt;function.json-encode&lt;/a&gt;]: Invalid UTF-8 sequence in argument /joomla/libraries/rokcommon/RokCommon/Ajax.php:93
  ...querySelector;}finally{if(!y){if(C){x.setAttribute("id",C);}else{x.removeAttribu...
  </code></pre>
  
  <p>Any help would be appreciated since everything I searched and tried didn't gave me positive results.</p>