With mesa 8.0 in Ubuntu 12.04 there is no more OpenGL support out of the box for cards missing DRI2 drivers. However, as was commented when the DRI1 support was killed off in mesa development, the old drivers can still be used with the new mesa core because the driver API has not changed. I have therefore packaged up old 7.11 DRI1 drivers into a libgl1-mesa-dri-legacy package for your ultimate convenience and retro enjoyment:

https://launchpad.net/~xorg-edgers/+archive/mesa-legacy

It works well on my savage laptop, that is, as well as OpenGL ever did on this card. I think the QT3 demo is pretty much how far it gets... I have no idea if the other drivers work, please report back if they don't.

Tips for old HW and SW:
- I often get page allocation failures when memory runs low. To save memory, boot with "text" and start X with xinit. If you are on Lubuntu, put "lxterminal& openbox" into your .xinitrc for a minimal desktop session. Otherwise, kill/uninstall all the daemons and applets you don't use (update-notifier, cupsd, printing-applet, blueman, etc).
- Some old third-party software looks for libGL.so. Make a soft link to libGL.so.1 or install libgl1-mesa-dev which ships such a soft link.