X11 and X11 applications won't start

Question

I seem to be having a problem getting the X11 application, which I installed from the 'optional installs' package on the OS X installation DVD, working. I originally posted this elsewhere, but was advised to post it here, where people familiar with X11 might be able to help.
I'll just quote what I posted elsewhere below, and hopefully someone can help.
I seem to be having a problem with the X11 utility, which I installed off of the OS X DVD (from the 'optional installs' package), and a problem with The Gimp, both of which i think are probably related.
Well I installed The Gimp a while ago, aswell as the X11 program, and both worked fine (you probably already know that The Gimp needs X11 to run). But at some point, it suddenly stopped working. I think it may have been after an update, but I really can't remember.
The problem I was having with The Gimp is that it would go to start up, but just after the X11 icon appeared in the dock, the cursor would change to an X for a few seconds. The splash screen would come up, but it didn't even appear to have a background or progress bar or anything, and didn't do anything.
At that point, just running X11 on it's own, or OpenOffice.org worked fine.
Well recently, i've tried to run The Gimp again, and something different happens. The X11 icon comes up and starts bouncing in the dock, but after a few seconds, it closes again, and The Gimp tells me that it needs X11 to run (which I already have of course).
When I try to run X11 on it's own, the same thing happens. The icon comes up in the dock, starts bouncing, then goes again.
I've used the Console program in the Utilities folder, and both times, for both problems (when The Gimp had the funny splash screen and wouldn't start, when it wouldn't start up at all, and when X11 wouldn't start), I get the same few lines which might help, these are below:
XFree86 Version 4.4.0 / X Window System
(protocol Version 11, revision 0, vendor release 6600)
_XSERVTransmkdir: Owner of /tmp/.X11-unix should be set to root
[DRI] screen 0 installation complete
Screen 0 added: 1280x1024 @ (0,0)
Could not init font path element /usr/X11R6/lib/X11/fonts/CID/, removing from list!
Quitting XDarwin...
So now, I have The Gimp that doesn't work, X11 that doesn't work, and OpenOffice.org doesn't work either (same problem where X11 quits), which is rather annoying, since I could do with using The Gimp.
I hope that explains my problem a bit, and I hope someone can help me sort it out. Thanks in advance for any help
Mac Mini   Mac OS X (10.4.3)   1.33 GHz Power PC G4, 512 MB RAM, 40 GB HD

Answer 1

I have a similar problem that I described in a different forum, but was referred to this one and hope that someone can give me clue.
My original message was:
Hello,
Brandnew here and new to the Mac environment (former Windows user), so excuse for anything dumb as it may follow.
Wanting to install GIS software (Grass GIS) it appears to require X11 application. Found the refence in Machelp to the topic on the Apple site. However, it doesn't provide a link to the actual software, just states it is on the Install disc. Indeed, there is a package on the install disk (under Xcode Tools/Packages) called X11SDK.pkg. I thought that this might be the required app, but after installation of the Xcode tools the Grass software still doesn't function (start-up screen only and error message indicating that there is no X11 found).
Thus the question is: how do I properly install the X11 app and where do I find the software?
I hope that someone can help me out (as the AppleCare helpdesk doesn't seem to function today). Many thanks in advance.
Bram