Unfortunately, 10.5 killed the nostromo.
I could have sworn that my friend had his working on his G5 running 10.5. However that was an n52 and not the original.*shrug*
Oh, I had an n52 as well. Maybe it was Intel's fault!
Someone was writing custom drivers for the Nostromo at some point, I wonder if they ever got finished.
Otherwise, ControllerMate would likely handle it, if $30 is OK. I upgraded my USB Overdrive and it supports a lot more devices no so maybe that will work also.
Edit: I think I'm completely wrong, and Belkin eventually released a new version of their drivers since the last time I looked.
I use my N 52 on my MacBook and my iMac both are Intel systems and there was a long time that they didn't have a universal driver that worked on the Intel Macs but they released one about a year ago. Hope it works for you.
Here is the page for their drivers:
http://www.belkin.com/support/article/?lid=en&pid=F8GFPC100&aid=5234&scid=0
