Something that i haven’t find via goole. By default on RedHat (and derivatives) if you get a dark background the colored ls will be seen really humm bold from a xterm (since i guess there default gnome-terminal has been configured to have a white background ).
The solution is to
cp /etc/DIR_COLORS /etc/DIR_COLORS.xterm
or to redefine your dircolors to get the /etc/DIR_COLORS files instead of /etc/DIR_COLORS.xterm in your shell init configuration.