panic after rebooting with geom_mirror on 8-CURRENT i386

[Aryeh Friedman]

I followed the steps in the handbook for mirroring the disk:

1. Installed an identical drive
2. Did all the pre-reboot steps in the handbook
3. On rebooting I get:

  a. bootloader works fine
  b. The kernel finishes the device probe
  c. (On first command in /etc/rc [or even loading the file]???) I get
a kernel panic saying "Divide error in kernel mode"

I do not have uname -a but it is 8-CURRENT i386.  The kernel is within
the last few days.   I do not have debugging enabled in the kernel.