[Grml] vim, grml 0.9 on hd - strange characters after using backspace

[Frank Eisenblaetter]

I have a strange problem with vim. When I use backspace to delete some
characters while I am in instering mode, there appear blanks or other
characters which I definitely not typed.

example:

[a], [backspace], [a] results in the folowing character

å

Maybe it has something to do with unicode. I use unicode_start in
/etc/zsh/zlogin.

Regards,
Frank