To be honest : I'm very surprised this Game even runs on the Voodoo5 in the first place...
(which means that the SFFT Driver is already doing one heck of an awesome job)
On higher Details, it is known to drag even quite high-end Systems quite a bit down
That it won't run on non-SSE Systems is weird though...
I think Koolsmoky wrote a small nifty Utility that fakes SSE and reroutes its calls onto the normal FPU.
I'll have a look around, see if I can still find it (I think he made it when ATI owners managed to run the NVidia "Dawn" Tech-Demo some years ago)
-- edit --
Found it, but it was only a special glu32.dll to work exclusively for that Demo, so it's unfortunately not a general purpose Utility.
-- edit 2 --
I've launched an EMail to query Koolsmoky. No Idea if it gets through, but at least it's worth a try.
(alot of people have the SSE requirement Problem)
-- edit 3 --
Now I got it, it was coded by Colourless... I'll ask him then
(he managed to re-route SSE Calls onto the Athlon 3dNow! ALU it seems, worked like a blast for the Dawn Demo)