Wordpress 3.1 makes my drop down menu dissapear, jquery dont work

Question

Please help,

After i upgrade to WP 3.1 just now, all my site menus not working, no drop down menu, and the jquery countdown not working. please help me.

Answer 1

Make sure you're not accidentally loading jQuery 1.5.0 from somewhere like Google's CDN or something. jQuery 1.5.0 is not backwards compatible, and the timing of its release prevented it from making it into WordPress 3.1.