Installing Jenkins on FreeBSD is now as simple as:
# cd /usr/ports/devel/jenkins/
# make install clean
This will automatically install Tomcat if you haven't already got it installed, and of course Java. Jenkins supports the standard Java 1.5 and 1.6 ports available on FreeBSD at this time, including Diablo (the precompiled Java). It is no longer necessary to install Linux Java. FreeBSD 4.9 can be made to work as well, but you will need to compile your own JVM.
If you have any problems with the resolution of conflicts in the installation of dependencies, use portupgrade:
cd /usr/ports/ports-mgmt/portupgrade
make install clean
portupgrade -N jenkins
Once you've installed and laucnhed Tomcat, jenkins will be available at:
You can specify a another tcp-port directly to the "/usr/local/etc/rc.d/jenkins".