Resizing icon does not always show
When double-clicking on a bar line, a small, blue square should pop up to indicate that the user may resize the bar. Only about 30 percent of the time it does so, however. The bar is always adjustable when double-clicked, but the box is not always shown. If you know where it is, though, and click and drag where it should be, then it will eventually appear. If one were to click on a blank space after double-clicking, the blue box would flash as if there all along, then disappear.
Ubuntu 9.04 Jaunty