Can't backspace password (e.g. su and ssh password) on Xterm
I have a problem with inserting passwords in Xterm. I used to use KDE and Konsole, and never had any problems; recently, I switched to Fluxbox and xterm, and since then I haven't been able to use the backspace key when typing passwords, that is, when I try, I always get a wrong password error, as if it didn't delete the previous characters but add new ones. My idea is that the password-reading program is not able to decode the characters representing backspace, but I really don't know how these things work.
I thought it could be a problem related to Termcap, since on Xterm I use the "xterm-256color" terminal and on Konsole I probably used something else, but I made some tests and I think that's not the issue: in fact, using any terminals (i.e. "linux", "xterm-256color" and "xterm"), when I use Xterm I experience this problem, whereas when I switch to a non-X console (by pressing Ctrl-Alt-F2, for example), using the same terminals, it works correctly.
So, it seems to be something related to Xterm. Also, this only happens when typing passwords; otherwise, the backspace key works fine.
Does anybody have any idea about this?