Hi rdworth,
Your solution works great!
Two things I would like to admit.
1. With this solution, drop is rejected if draggable (helper) is outside scrollable region. But, with this solution draggable just disappears from the screen. What expected is, draggable-helper should be reverted back to its original position as I have set [revert: 'invalid'] in draggable initialization.
2. The problem mentioned in this post looks like a problem with jquery ui; so, shouldn't it be handled by jquery ui javascripts itself. Can it be raised as an issue so that it can be fixed in next jquery ui releases?
Thank you very much for your time,
Any other pointers from others would be good.
Bhavnik