As root on the console (not X), start screen, then run vim inside screen.
Enter some text, then press the backspace key. It displays a literal "^?"
instead of actually backspacing. Note this doesn't happen when doing this
from X or as any other user.
This happens to me when I "su" to another user and then run vi.
Note that it happens only for "konsole" and not for "kvt".
Maybe something wrong with the xterm terminfo.
Looks like the "screen" termcap and terminfo were out of sync; I can't reproduce
it w/ ncurses 5.1-5+termcap 11.0.1-3 anymore.