I have written custom classes for IIS, v 6.X , and they don't seem to be working

Question

I have written a couple of custom php classes that are deployed to IIS servers.

They work fine on the development box but not on the staging server.

I don't have much experience with IIS and am not sure if it's a config issue with IIS or a something to do with the php.ini file.

Any hints would be appreciated.

Sorry for being vague.

I have written two php classes that are then implemented by other PHP docs in a site creating instances of the object and sourced by include files.

Here's an example, I have the following class: class ReportManager extends Stemmer

I then include it in a php doc: include_once("./standards/class/class.reportmanager.php");

The calls to member methods etc work fine on the development box but not on the staging server:

Instance: $RM = new ReportManager();

Method Call: $RM->userIsActive($this_user);

...works fine on the dev box, not on staging bith IIS.