Create a php script with the following code:
<?php phpinfo(); ?>
Open it in a browser and it will give you detailed information about the PHP configuration on that server. Two things that would indicate a mod_php install would be:
At the top look for "Configure Command". See if it contains '--with-apxs;
Under the 'apache' section find the "Loaded Modules". See if it contains 'mod_php4'
If you answered yes to both you definately have a mod_php4 install.
