I had the same problem for a while, I'm using a FreeBSD box (6.0 release) running with AMD processor, with Apache 1.3.33, Mysql 5.0 and PHP5.0.4
When trying to run the config script/page I was getting that nasty "Fatal error" about the preg_match function, so I went to dive in the inet to try and get a solution.
After tons of reading I found myself faced with the PCRE problem, but I had PCRE 6.2 installed, so the problem needed a deeper thinking as the problem seemed to be the order of the installations or, maybe, the lack of more packages.
To briefly resume what I did to finally get my PHPBB forum working:
- Deinstalled PHP5.0.4 (pkg_delete)
- Downloaded the packages again: php5-5.0.4_2.tbz and php5-pcre-5.0.4_2.tbz
- Installed (pkg_add) first the php5 and then the php5-pcre
Restarted (apachectl graceful restart) the Apache server and GOTCHA !
Hope this help a bit
Learning something new everyday...