VIVE L’AMOUR!
I quote my previous mail about ROOT v5-18-00-patches svn source code … 
The “newest” compiler, that I was able to use, was gcc 4.2.1 (openSUSE 10.3, i586). <img src=“/uploads/default/original/2X/8/84c2fe9464a4066c00e1bd5978e913e7869cbb07.gif” width=“22” height=“16” alt=“:-”" title=“Whistle”/>
Later, I was NOT able to use gcc 4.3.2 (openSUSE 11.1), NOR gcc 4.4.3 (Ubuntu 10.04.1 LTS, i686). ](https://root-forum.cern.ch/uploads/default/original/1X/76db2ba49fab631d84524c020356bc148461ca74.gif "Brick wall"){kind=small}
Well, you might try to get the Ubuntu “root-system” 5.18.00 version configured with Qt3 and then compile it (though I do not know how many official ROOT patches from snv are in, I have never tried to compile it myself):
https://launchpad.net/ubuntu/+source/root-system
https://launchpad.net/ubuntu/+source/root-system/5.18.00-2.3ubuntu7
http://archive.ubuntu.com/ubuntu/pool/universe/r/root-system
If you decide to use the standard Ubuntu “root-system” binary packages (I was using them, but I did not care about Qt add-ons, and they configured it with Qt4 anyhow, I believe), make sure you execute:
export LD_LIBRARY_PATH=“/usr/lib/root/5.18:${LD_LIBRARY_PATH}”
This is because they have a problem in the “root-system” configuration. Some libraries are in “/usr/lib/root” (that’s what you get when you try “root-config --libdir”), but some libraries are only in “/usr/lib/root/5.18”.
BTW. The “linux = i386 Linux” target if fine for your “i686”. It’s the compiler which will decide what “target” it really uses. Try “gcc -v”, you will see something like “Target: i586-linux-gnu”, for example. 
A pitiful case, am I not?
Pepe Le Pew.