How do I make text wrap nicely within non-rectangular shapes, such as the majority of shapes in the stencils that come with OmniGraffle 4, such as circles, diamonds, trapezoids, etc.

Currently, even with "Wrap to Shape" checked and the "Resize to fit" mode selected for a given shape, text will still leak onto and beyond the edge of the shape, because the text-wrapping algorithm is apparently treating all shapes as if they were rectangles.

If this is a bug you need to address, I'd make it a very high-priority one, please! OmniGraffle is otherwise impressive as a tool for producing nice-looking diagrams, but text spilling over edges is a pretty fundamental problem.