I have 2 local users on one host, both running with /bin/bash, I compared the env and locale settings and both are the same. But I still get these symbols "•••" on the test user while I'm pressing backspace, delete or arrow keys in vim if I'm on top or bottom. .bashrc also looks like the same of the productive user and I'm also using the same SSH connection settings via rebex.
Anything else what I forgot to check?
I solved the problem by clearing the cache, there was a kind of bug in RemoteDesktopManager, because normally the session should be refreshed every minute.
Like I told in the comments, I got on the same PC, with same settings, on one of two users on the same host, some kind of symbols. Same settings on another PC still works, so there wasn't any problem with xterm, bash or vim.