How to manually start firewall after system completed boot.

[Joe]

I have special purpose situation where I need to wait until the boot 
process has completed the starting of the system and then start the 
firewall (ipfw or pf). Commenting out the firewall statements from the 
hosts /etc/rc.conf does stop the firewall from starting at boot time.

Is there some format of the service command that could be used to 
manually start the selected firewall?

Any ideas on how to accomplish this is welcome.

Thanks