Before I lose it again, let me praise the apt installation package. In comparison to "yum", this software seems to work effortlessly; upgrading to the latest and greatest Ubuntu distribution ("jaunty jackalope") was just a pleasure. Almost.
That's right, almost. You see, I decided to use my spiff Linotype scanner. And you see, that requires the sg kernel module. No problem you cry! Why it's just "modprobe sg". Not so fast. There isn't a sg.ko in /lib/modules anymore! Say what? Did it go away? After downloading the kernel sources (yes, I did that), I regret to say that guess what? You guessed it. The sources are there. As it so happens, I have the kernel headers. So, I stripped out the sg code and compiled it. Minor complaint but I get a .ko; and what happens when I modprobe it? You guessed it, didn't you? It didn't load.
A posting on the Ubuntu bugs list is of course ignored. Need I say more? It's linux, isn't it?