Call to undefined function preg_match()

Greetings
Have searched high and low and cannot find another with the same problem. Here goes.
Windows 2000
PHP 5.0.4
MS IIS web server

I just downloaded and setup PHP 5.
I have a few php scripts that do run from both the CLI and the localhost web server.

Problem is that a script that uses the preg_match() function fails. Error is :"Call to undefined function preg_match()". I have researched the PHP site (among others) and found that this function is part of PCRE (Perl Compatible Regular Extensions). There are several references to this problem related to unix systems where the php5-pcre port has to be installed. However, the PHP web site states that this function is supposed to be built into php5 and that no php.ini changes need to be made to make it work. well, it doesn't work.
I have all PHP files in CHP and the extensions are all located in the sub dir CHPext.

Any ideas?
Jeff

I dont have the general answer for you but i do have a lead that might help you if you keep on investigating this problem

I had the same problem running php-4.4.0-r1 on gentoo and when i installed the mod_php-4.4.0-r1 from scratch and upgraded my apache to apache-2.0.54-r31, using the same php.ini and apache2.conf i just had to restart the apache and everything came back to sanity level.... ohhh.. the problem is related to pcre so i did install some pcre c++ libs that i thought might replace to defective regex functions

anyways... good luck jim