... and it's driving me insane.
Basically (this has been happening over the past couple months), I log into a few different CentOS servers (one Linode, another VPS, and a shared host to which I have shell access), running 5.5, 5.7, and 6, from my Mac running OS X Lion, using Terminal.
$ ssh email@example.com [remote-host] $ nano somefile.txt
Once I start editing the file, if I use the arrow keys to move around the cursor, or start deleting, then typing again, the cursor jumps around a bit, and if I save the file and reopen it, it's obvious that the cursor was, in fact, jumping all over the place on a line for no apparent reason.
I end up getting things like "This is a neof text." When I had typed in (to the cursor-crazy editor) "This is a line of text."
It's a big problem when it comes to editing configuration files, because I often have to edit one line, save and close, then reopen just to make sure that line is right... then edit another line... and it's getting quite annoying.
I found Linode Lish Shell Vim and Nano rendering troubles: lines not appearing / cursor positions wrong, but I don't know if that relates much, since that's specifically referring to lish.