How to stream videos to iPad iOS 4.3 from iTunes

I have upgraded my iPad to iOS 4.3. When I tried playing the movie in iTunes 10.2.1 on my iMac and select the AirPlay menu, I can't find the iPad device. How can I stream a video to iPad from iTunes on my home network?* First make sure Home Sharing is enabled in the iTunes preferences on your computer.* On your iPad, tap Setting > iPod and enter your Apple ID informations under Home Sharing. *