On our network we've got a couple of Canon PIXMA network printer/scanner/FAX devices. Some versions of SANE apparently get confused trying to scan them with "network discovery" activated. The xsane application simply crashes.
After some searching on the web I have discovered what appears to be the fix. At least the fix has worked on a variety of Ubuntu 10.x machines, both 32-bit and 64-bit. I haven's saved the sources I used and can't locate them again so whoever was my inspiration on this one - please accept my apologies for failing to credit you.
So, be it as it may, here's the fix. Got to /etc/sane.d and edit the following file: epson2.conf . Comment out the following line:
You are done.
Final notice: after yet another round of updates on a 64-bit Ubuntu 10.10 machine I noticed that even this fix is not necessary it seems. But on slightly different installations this tip may still be of use.