Having spent the last 4 or 5 days messing with setting up a build environment for the up coming Servo Controller design work I have finally got a method that seems to do what I want even though it appears to have a few installation glitches.
Most of my development environments are stand alone machines set up as Virtual Machines On a Ubuntu Workstation running VMware-Server. This makes it easier to backup/restore and ensures that one set of build tools and their upgrades has no effect on another.
The final model that seems to work (at least until I try and use it in anger) is Ubuntu Feisty (7.04) with the down loadable Xilinx netpack 9.2i installed as the development environment.
I needed to get the single file complete down load from xilinx even though it is huge. Installation proceeds relatively painlessly initially but does not give you the opportunity to enter a product code. As the installation progresses there appear to be 5 zip archive which won't uncompress these fail with errors and when complete xilinx's update utility fails part way through too.
When you run up the software though it looks to be a runner.
We'll just have to wait and see.