Php 5

Hi, i want to setup my forum witch currently requires PHP5 but the server is PHP4. Can someone tell me how to run php 5 on it? I tried the in and .htaccess file:

# # AV: php4-engine
AddHandler php5-av. Php

But it doesnt work :/ Help!

You can enable PHP5 by accessing your panel in the section AlterSite->File management and clicking on the gear in the left-top of the page. By doing this, you enable PHP5 on the directory currently displayed in the file manager.