jQuery problem on QWebView

I am currently evaluating whether Qt can be a proper platform for hosting HTML based application. My current app works on Adobe AIR. However I am not very satisfied with its Webkit rendering (especially the text and form elements). I tried fancyBrowser on various URL. It looks to me the JavaScript speed on Qt-Webkit is kind of slow. Google Map can't finish loading from time to time. What worries me most is it even failed some jQuery demo pages. For example jQuery effect doesn't work: http://jqueryui.com/demos/effect/ . I am using Qt4.6.2 on Windows. Does anyone have similar experience or did I miss anything? I really like the text rendering on Qt-Webkit and all the native look and feel Qt offers. It's a pity if it can't fill its promise on such simple thing as executing JavaScript. Is Qt a feasible alternative to Adobe AIR for hosting HTML app? Any input appreciated. Thanks.