I just switched one of my systems from Gentoo to Ubuntu. There is one difference between the two setups that is driving me mad, and I cannot figure out how to fix it. When I use the 'up arrow' to go to a previous command, the cursor is moved to the start of the line. In Gentoo the cursor would remain at the end of the line. I have been using this behavior for over 10 years, adapting to the new behavior will be a major pain. How does one configure this?
This happens in any terminal: urxvt, xterm, and the console before X starts. It happens in bash and zsh, and happens regardless of if I am using 'screen'. It seems to be a global setting.
With respect to zsh, in debian, therefore in ubuntu too, it seems to be caused by the global zshrc settings (/etc/zsh/zshrc).
I've been looking for this for a while. Today I wrote to the zsh-users list and got the answer: http://article.gmane.org/gmane.comp.shells.zsh.user/12079
There's even a debian bug about it: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=383737
Though I don't have a Gentoo installation available I am going to guess that what you have described is almost certainly related to your readline configuration.
A quick scan through the man page indicates this option which looks close to what you might want.