On a 2.0 laptop, the system won't boot properly with a USB keyboard 
connected.

To be precise, the machine is a Thinkpad R51; the keyboard is a compact 
IBM PS/2 keyboard, hooked to the machine via a Belkin PS/2-to-USB 
adapter.  (R51s have no integral PS/2 ports.)  The keyboard is 
recognized as such by the BIOS; at least, one can talk to the NetBSD
boot prompt with it.

The problem occurs while it is probing the USB space -- it hangs when 
it gets to that device.  Has anyone seen this?  Any fix for it?

		--Prof. Steven M. Bellovin, http://www.cs.columbia.edu/~smb