Ok, I'm not getting it.
PHP has an apache module - mod_php.
Perl has an apache module - mod_perl.
Neither require spawning external processes to byte compile the scripts. They are read in once at init, and you go.
The apache benchmarking tool has shown WWWThreads 4.4.1 capable of handline 100 page requests/second of wwwthreads.pl w/3 categories and 20 forums on a 360 Mhz Solaris 2.7 machine running apache 1.3.9 and mod_perl.
This can be scaled up fairly quickly using a seperate machine for the MySQL server from the web server and using a non DNS based load balancer.
Don't get me wrong, PHP has it uses. I looked at using a number of PHP boards before settling on WWWthreads last year. WWWThreads was by far the superior solution. It had the richest feature set provided and the cleanest UI PLUS its backed by MySQL. For the life of me I can't figure out why so many sites use UBB...
I question your rationale of claiming that WWW threads needs to be ported for speed considerations.