Have you tried it so that you can so categorically state that it is impossible? I have. Don't you know what the word "emulator" means? Please don't advise people what they can't do if you haven't tried it yourself.
I have run Windows 98 in qemu on a PPC Mac Mini. Qemu emulates the x86 processor, hence the name "emulator" which is why it tends to be a bit slow on a Mac. Qemu can also emulate PPC, Sparc, and ARM processors.Here's a link
to Q, the OS X version of qemu.