Import the core parts of the DTrace patch. This is a modified and updated version of what was submited by Theo before: <http://mail-archives.apache.org/mod_mbox/httpd-dev/200805.mbox/%3C6AFBCFE8-4CCA-4A02-8A43-F9170689695D@omniti.com%3E> Note, this does not hook it up into the build system at this time, because the original patch was a little too creative there. Submitted By: Theo Schlossnagle <jesus omniti.com>