sudo and graphic apps not working

English Applications
#1

After upgrading GNOME to 2.32 in my openSUSE 11.3 x86_64 running graphic applications with sudo is impossible. (that means it worked before upgrading GNOME)

etam@etam-laptop:~> sudo xeyes
root's password:
No protocol specified
Error: Can't open display: :0.0

From /etc/sudoers:

Defaults env_keep = "LANG LC_ADDRESS LC_CTYPE LC_COLLATE LC_IDENTIFICATION LC_MEASUREMENT LC_MESSAGES LC_MONETARY LC_NAME LC_NUMERIC LC_PAPER LC_TELEPHONE LC_TIME LC_ALL LANGUAGE LINGUAS XDG_SESSION_COOKIE XMODIFIERS GTK_IM_MODULE QT_IM_MODULE QT_IM_SWITCHER DISPLAY"

Some interesting facts:
“xhost +” fixes (or rather workarounds) this problem.
“xhost +127.0.0.1” doesn’t help

#2

sudo was never meant for running GUI apps, use

xdg-su -c xeyes

#3

or open your X display first to other local users with:
xhost + local: