OldgitTom, interesting that you can get your 10 years old Canon scanner to work...
I've tried what you did with my brand new (2012) Canon all-in-one printer/scanner i-Sensys MF4430 and it is impossible.
(Linux 13, Mate, 32-bit, Asus Laptop + sane, libs and simplescan).
There is an official PRINTER DRIVER on Canon website, but no SCANNER DRIVER.
I've sent a mail to Canon support, asking whether there might be a scanner driver somewhere, or a driver for another model but similar to mine.
Answer: "no, sorry".
So my all-in-one machine can only print under Linux. When I bought it 6 months ago, I was still under Windows and did not plan to move to Linux. But after an ultimate crash and many hours wasted, I've moved all my business to Linux, and now I would like to be able to do everything on Linux.
Sadly... it seems that I'll have to make a dual boot and reinstall Vista... JUST for scanning!
Well in fact, from a business perspective (and from a profit perspective), it would probably be cheaper to buy a basic scanner compatible with Linux and forget about my Canon printer scanning feature. If I take into account the number of hours required to install Windows, updates, etc... It will cost much more $$$ (or euros) than a new scanner.
But it is very annoying not to be able to use my beautiful machine. Moreover, I've spent a long time to choose it among other models because I especially wanted an all-in-one to gain space in my office...
Canon, never again.