upgrading 4.0 to stable

[Kristen Doyle]

I have done one from 4.5 to stable the easiet way is to use screen if 
you dont have a stable connection
in this order (make sure nothing else is running ie shutdown services 
except sshd ) and append the KERNCONF=blah
make buildworld
make buildkernel
make installworld
make installkernel
mergemaster -p
reboot
cross your fingers and hope:)
Ive had it fail only once