canvas newbie question

[Brian Swenson <bswenson fastlane net>]

I'm trying to figure out how the canvas works and I've been running into
problems.  I'm following the example in chap. 12 of GGAD and can't seem
to make the scrollbars work correctly.  When I compile and run the
example, I can scroll across the canvas area by either grabbing the
scrollbars or by clicking on the trough but when I click on the
scrollbar arrows nothing happens.  Do I have a configuration problem or
is the example missing something?  Any help would be greatly
appreciated.

Thanks,
Brian