jQuery mobile : jsonp request using $.ajax(), $.getJSON not firing callback function
===

I try to get json data from my web server but it didn't work.

    $.mobile.showPageLoadingMsg();
    //$.getJSON('http://localhost:8000/'+site+'/?format=json&callback=?', {}, function(){alert();});

	$.ajax({
		url : 'http://localhost:8000/'+site +'/?format=json&callback=?',
		type : 'GET',
		dataType : 'jsonp',
		jsonp : 'callback',
		success : function(){alert('success');},
		error : function(){alert('fail')}
	});

`$.getJSON`, `$.ajax` two method's callback function didn't firing at all.
What's the problem?

my web server's code

    response_data.append({
				'user_nickname' : post.user_nickname,
				'title' : post.title,
				'recommend' : post.recommend,
				'oppose' : post.oppose,
				'date' : str(post.date),
				'hit' : post.hit,
				'commentcount' : post.commentcount
				})
		return HttpResponse(simplejson.dumps(response_data), mimetype='application/json')

in insepecter, it returns `get`, 200, ok, so `HttpResponse` has no problem.

Here is response

> [{"hit": 5, "title": "</table>
> \uc624\ud1a0\uc774\uc2a4\ucf00\uc774\ud551 \ub418\ub294\uac00",
> "commentcount": 0, "oppose": 0, "recommend": 0, "date": "2012-07-24
> 07:01:22.453000+00:00", "user_nickname":
> "\ud55c\uae00\ub85c\uc5bc\ub9c8\ub098\uae38\uac8c\uae4c\uc9c0\uac00\ub2a5\ud558\ub7ef\uc778\u3131\u3147\u3139\u3147\ub05d"},
> {"hit": 4, "title": "\uc5ec\uae30 \uae00\uc4f0\uba74?",
> "commentcount": 1, "oppose": 0, "recommend": 0, "date": "2012-07-24
> 06:52:05.125000+00:00", "user_nickname":
> "\ud55c\uae00\ub85c\uc5bc\ub9c8\ub098\uae38\uac8c\uae4c\uc9c0\uac00\ub2a5\ud558\ub7ef\uc778\u3131\u3147\u3139\u3147\ub05d"}]


`$.ajax()` never firing success's callback function. it just call error's `alert();`
