Re: system call incompatibilities across releases

[buhrow%lothlorien.nfbcal.org@localhost (Brian Buhrow)]

        Hello.  In general, you boot a new kernel, run etcupdate, then install
the new binaries.
If you had booted the 3.0 kernel with your existing 1.6 binaries, you
still would have been able to log in because pam didn't become an issue
until you actually installed the 3.0 binaries.  The trick was to run
etcupdate after you boot the new kernel, and before you install the new
binary sets.
If you do that now, to go from 3.0 to 5.0.1, you should be in good shape.
New kernels can run old binaries, but not vice versa.

Hope that helps.
-Brian