Richard,
Welcome to the wonderful world of FreeBSD. FreeBSD-5.1 is not "release"
code. It is "alpha" quality (thought pretty good quality as Alpha goes).
I understand that the website doesn't make this abundantly clear on the
homepage. FreeBSD 4.8 is the current production quality code. It will
probably be much faster for you as well, since debugging options are
turned off by default. You can get from 5.1 to 4.8 without having to
reinstall the OS by, well, reinstalling the OS.
By following the instructions in the handbook for "upgrading" you can
also "downgrade" to FreeBSD-4.8 by downgrading your source tree in
/usr/src, building and installing world. It's actually not quite as bad
as it seems in the docs and I've managed upgrades and downgrades with
minimum of downtime. Most of the steps can be done while the system is
running. The steps that should be done in single user mode (and I
recomend this since your not familiar with FreeBSD yet) are pretty quick.
FreeBSD is actually fairly nice once you know what's going on.
The Handbook is
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/index.html
and the chapter you want is
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/cutting-edge.html
Substitude "old" for cutting edge and your on your way. The CVS tag you
would want is
RELENG_4_8
I would recomend rebuilding anything you built in ports after you
upgrade the system, since this downgrade is considerable, but again much
of that compile time will be while the system is running.
Your really only looking at the time to do a make install and make
installkernel, and rebuilding the database server as your downtime. Much
less considerable than reinstalling an entire OS and getting everything
installed that you want.
If you need more assistance shoot me a line, off the MySQL list (as it's
no longer a MySQL issue) and I'll answer what I can.
--
Michael Conlen