>I have successfully used a similar method to Andrew Brown for dynamic
>OS upgrades - with a minor variation prior to the kernel build;
>
>  in the usr directory I replaced more directories;
>    lib libdata libexec bin sbin games include mdec obj share

well yes, of course :).  include and libdata need to be done at the
same time as well.  the others are somewhat less version critical.

>Once these were in place, the host (a firewall) continued running
>without a problem for the next 8 hours, until it was convenient to
>reboot with a new kernel.

...but since you had installed the new kernel, the only thing
remaining was to actually tell the machine to reboot, yes?

-- 
|-----< "CODE WARRIOR" >-----|
andrew@echonyc.com (TheMan)        * "ah!  i see you have the internet
codewarrior@daemon.org                               that goes *ping*!"
warfare@graffiti.com      * "information is power -- share the wealth."