The pc/104 (correct me if I am wrong) defines the form factor and a bus, but not necesarily a cpu type. I've never used these toys, but I've seen around pc/104 pieces with a pentium and many other processors, for example here: http://www.fastwel.com/products/3560...04/cpumodules/
So it all comes down to the type of cpu that your 104 has. As far as I know linux can emulate an fpu when there's none, but you might need to look around a bit or make your custom distro compiled to fit that hardware.
If you really lack an fpu, I would assume your cpu is an early 386 (386 sx, which is damn old, like late 80s/early 90s or so) so I'd start by looking here:
But first you should confirm which kind of cpu the critter has.