If you are using a DD-WRT firmware on your Wireless router you had probably seem that your iPad (or iPhone 3GS/4 using WIFI) have problems streaming Netflix movies. The main issue is that when you select the movie that you want to see on your iPad Netflix application the movie start to load and then after few seconds it goes back to the original screen and the movie never loads.
The solution it's to disable DNSMasq in you router's basic setup configuration screen.
Here is how to fix it:
1- Point your browser to your router's ip address: e.g. http://192.168.1.1 and enter your administrator user and password.
2- Select Setup – Basic Configuration and at the DHCP section uncheck "Use DNSMasq for DHCP" and "Use DNSMasq for DNS"
3- Save and reboot your router.
4- Now Netflix applicati0n on your iPad/iPhone should work with WI-FI.