Please extend a new special method to load your form data.
<script type="text/javascript">
$.extend($.fn.form.methods, {
loadRemote: function(jq, param){
return jq.each(function(){
var f = $(this);
$.ajax({
url: param.url,
data: param.params||{},
dataType: 'json',
success: function(data){
f.form('load', data);
}
});
})
}
})
</script>
Usage example:
$('#fm').form('loadRemote', {url:'getItem.ashx',params:{itemId:'itemId}});