Issue with jQuery in wp3.2

I’ve add lazy loader to my installation and after upgrading to 3.2, it doesn’t work correctly.

After some tests, I’ve found it’s caused by the jQuery Library included in WP installation.

If I use wp_enqueue_script('jquery');, it doesn’t work.

After uploading the official jQuery1.6.2 to my server and switching to <script type="text/javascript" src="***/jquery.js"></script>, it works again.

So I’m wondering if it’s because the jQuery1.6.1 delivered with WP3.2 has some problems or it’s because I misused wp_enqueue_script().