Well, after Juan's quick fix to amd64/machdep.c (rev 1.68) my kernel 
boots again!

Even better, the previously-repeatable crash-on-xterm-exit has taken a 
vacation too.

Thanks for the quick resolution.

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|   Paul Goyette   | PGP DSS Key fingerprint: |  E-mail addresses:   |
| Customer Service | FA29 0E3B 35AF E8AE 6651 |  paul@whooppee.com   |
| Network Engineer | 0786 F758 55DE 53BA 7731 | pgoyette@juniper.net |
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