IE scrollbar weirdness

Scroll bars in IE disappear and can get set to the wrong height.

When editing an asset in IE 7, the window often comes up with no scroll bar (See screen shot 1). If you then reduce the window the scroll bar appears, and if you expand again, it is there and positioned correctly.

If you then reduce the window size and then edit a wiki block (Or possibly other blocks) and save OR cancel, then expand the window, the scroll bar will be stuck at a too short high (See screen shot #2)