title: when checkbox is checked, wrong value is submitted for the property
body: <p>In the jqgrid, the column is defined as following:</p>
  
  <pre><code>  {name:'production', index:'production', width:60, align:'center', formatter:'checkbox',editable:true,edittype:'checkbox',editoptions:{value:"true:false"},formoptions:{ rowpos:10,elmprefix:"&amp;nbsp;" }},
  </code></pre>
  
  <p>Generated html for the edit form is the following:</p>
  
  <pre><code>&lt;input type="checkbox" value="true:false" offval="false" id="production" role="checkbox" class="FormElement"&gt;
  </code></pre>
  
  <p>So when the checkbox is unchecked, the correct value 'false' is submitted, but when the checkbox is checked, 'true:false' is submitted, which is obviously wrong. I would want 'true' to be submitted. What am I doing wrong?</p>
  
  <p>Thanks!</p>