How to drag in the web browser without moving the page? With the stock browser when using a web page has a feature that requires dragging, how do you drag without moving the page?  

For example, cropping an image on the Gravatar site requires dragging the boundaries, but whenever I try to, I end up moving the page... but not dragging.

UPDATE: I did notice on a third-party page with Google Maps embedded that the map did drag correctly.  However, the above example still holds.
With sites like Gravatar or Twitter's image cropping, I've found that the two finger "pinch" gesture works.