8.1 Apache 1.3.26 - Old Libphp4.so Howto Upgrade?

Hello,

i have following problem:
We use here in the company a test server running on SuSE linux with Apache 1.3.26 from standard 8.1 Installation and its PHP module. (libphp4.so) in /usr/lib/apache.

We require now the newest php version for some specific tests on devices and i wish to change as few things as possible as this server (test server) is used to validate other products.
I would like to only update the php module to the newest version.
How can i achieve this easily and smooth ? (only PHP, no interest to upgrade apache atm if possible)

Thanks for your help in advance,

greetings
nirax