Can't use touches, accelerometer in UIWebView w/ local html

I'm using a UIWebView to display a local index.html containing Javascript. I've noticed that touch events never register, and the code snippets I found for getting the accelerometer values doesn't work either.

For example, this: Move the Ball

When I view that page in (mobile) Safari it works fine. But if I save the source locally and load it in a UIWebView, it doesn't work in the app. Same thing goes for examples that use touches!

It's as if the UIWebView was set to "display" only, with no user or hardware interaction. I see this both on the device and in the simulator. Any ideas?