not upgrading, just recompiling

[Aaron Peterson]

I have changed my optimizations in make.conf (fbsd4.8) and would like to
recompile everything (just because it comforts me to have something
compiling at all times).  I have found portupgrade etc...  to help
upgrade packages but really what I want is to recompile all the packages
I've installed in bulk.  "cd /usr/src && make buildworld && make
installworld" gets only part of the job done right?  just the base
system?  then how can i do installed ports?  is there some simple
command i can use (or maybe two?)  i'm sure i could write some perl
script to read pkg_version and go do things, but surely someone has
already written a utility to do this type of thing...  Obviously i'm not
a fbsd veteran :)

thanks in advance...