Problem enabling xsl in php

I have a server with php5 installed on it. I need to enable XSL on it. when I try phpinfo(); I don't see anything related to XSL. I already have "libxslt" installed.

Is there a way through which I can upgrade my php installation to have xsl support? I don't want to reinstall php.

I thought of adding extension=xsl.so to php.ini but I don't know if I have xsl.so there and where it is! but does that work?? if yes I have to figure out where xsl.so is or download it if that's possible.

Please help me because this is my first experience in a real working environment.

BTW: The server OS is Linux (a property distribution base on RPM).

UPDATE:

I tried the following method but still can't enable xsl or see any difference in phpinfo():

1- decompress the php source code and cd to the directory of the extenstion i.e. cd /path/to/php/ext/xsl

2- phpize

3- ./configure

4- make

5- then move the xsl.so to the extension_dir

6- restart apache

I found this on many forums and blogs online but I don't know why it didn't work with me. Any help is still appreciated.

I finally could enable XSL without recompiling the whole PHP, using phpize command:

How to enable php extension using `phpize`?

the most important thing is enabling DOM extension before compiling the XSL extension and enabling it..

Thanks