Great job!! I'm reading the paper, looks very good.
I'm working in SMP support, using xAPIC (32 bit yet). Your work makes more sense to my project :-)
I haven't been working on Hurd for the last year or so, but I do pop in and browse the mailing list from time to time, so I am aware of your work.
If Hurd's going to be a player on the operating system stage, we obviously have to get SMP (and 64-bit addressing) working, or we won't be taken seriously.
So, you're doing the "grunt work" to move this project forward, and I applaud your effort!
agape
brent