Pages can't be dragged as a child of another page

[Soma]

As title already says. When I want to drag-move a page as a child of a page that has no childs yet, I can't. Even if the target page has childs but isn't opened, I can't move it.

[ryan]

In order to drag-move a page to another branch, you have to open that branch first (even if it has no children). Opening that branch is a matter of just clicking on the page. You know a branch is opened when you can see it's 'edit | view', etc. links. I think it would be nice to have it auto-open a branch when you hover over it for a couple of seconds, but that's beyond my current JS skill level.