The "solution" to this first part was to stick with an old version of the driver until the next Ubunto long-term release. :(
After all that hacking, my nice GPG interface went away. It used to have:
- A pretty gnome-looking window for entering password,
- Short (like 15-30 minutes?) cache time for future gpg commands
- A little tray icon with a lock I could use to clear the cached pass phrases.
That's all gone. pinentry-gtk2 simply doesn't work. When installed, it flashes up a window, which accepts no input, and then disappears leaving a "bad passphrase" message on the terminal. The little tray thing is also gone.
The "solution" to all this is the pinentry-qt package, which pops up a KDE-looking window for entering the password. Lacking the system tray icon, I've found that sending a kill -hup to the gpg-agent directly will make it dump its cache.
So at least things are kind of working.