window position freezes when using multiple monitors

[GoogleCodeExporter]

- What steps will reproduce the problem?

1. run acme-sac.
2. drag window onto non-main screen (left of main screen)
3. maximise acme window
4. drag half way onto main screen.

- What is the expected output? What do you see instead?

the window now cannot be moved. minimising the window
and un-minimising it cures the problem (but that's no
good if the top right of the window is not visible,
in which case the only cure is to exit acme).

- What version of the product are you using? On what operating system?

acme 0.11 under windows XP.

- Other info:

workaround seems to be to make the window bigger by dragging the edges,
rather than by clicking the maximise button.

Original issue reported on code.google.com by rogpeppe@gmail.com on 20 Mar 2008 at 3:23