Difficulties when switching to root

[Virchanza]

OK I now we have "sudo", which is fine for doing one command at a time, but sometimes I need to do lots of stuff (especially when playing around with networking), so I find it handier to switch to root by doing:

virchanza:~$ su
Password:
root:/home/virchanza#

But here's the problem. Look what happens if I try to open Kate after having switched to root:

root:/home/virchanza# kate &
[1] 5924
root:/home/virchanza# exit
virchanza:~$ The program 'kate' is currently not installed.  You can install it by typing:
apt-get install kate
bash: kate: command not found

First of all, it couldn't find Kate.

Secondly, it mysteriously typed "exit" and switched me back to my normal user.

So I tried it again:

virchanza:~$ su
Password:
root:/home/virchanza# kate &
[1] 6017
root:/home/virchanza# The program 'kate' is currently not installed.  You can install it by typing:
apt-get install kate
bash: kate: command not found

[1]+  Exit 127                kate
root:/home/virchanza#

This time it didn't kick me back to my normal user, but still it failed to open Kate.

So let's see what happens if I give it the full path to Kate:

root:/home/virchanza# /opt/kde3/bin/kate &
[1] 6163
root:/home/virchanza# No protocol specified
kate: cannot connect to X server :0.0

[1]+  Exit 1                  /opt/kde3/bin/kate
root:/home/virchanza#

Also let me try Kcalc:

root:/home/virchanza# /opt/kde3/bin/kcalc &
[1] 6195
root:/home/virchanza# No protocol specified
kcalc: cannot connect to X server :0.0

[1]+  Exit 1                  /opt/kde3/bin/kcalc
root:/home/virchanza#

It looks like there's two problems:
1) Firstly it can't find programs like Kate and Kcalc, which I presume has something to do with the path environment variable
2) It can't connect to the Xserver

Anyone?

[sud0x3]

I had troubles with this on another box, just type sudo su, enter password. Worked fine for me after that.

[Miland3r]

With Backtrack4 being Debian (Ubuntu) based do the following to get kate working in a "su -" Konsole:

xhost local:root
su -
export PATH=$PATH:/opt/kde3/bin
export DISPLAY=:0.0
kate