[Plugin: NextGEN Gallery] Conflict with PHP

The “Overview” page of the NextGEN plugin posts the following warning:

NextGEN Gallery contains some functions which are only available under PHP 5.2. You are using the old PHP 4 version, upgrade now! It’s no longer supported by the PHP group. Many shared hosting providers offer both PHP 4 and PHP 5, running simultaneously. Ask your provider if they can do this.

However, the cPanel admin page for my ISP tells me that I am using PHP version 5.2.9. Is there anything I can do to help the plugin recognise that I am using the correct PHP version? The plugin is not working otherwise, as the slideshows do not appear at all on my pages.

https://www.ads-software.com/extend/plugins/nextgen-gallery/