Library's parameters load with MAMP, but will not load when placed on server?

[eluser]elvis2k[/eluser]
Newbie first post. Any help is much appreciated!

My custom library's parameters will not load when on a server, but load fine when using MAMP.

I have written a custom library which lives in:
application/libraries/MYcustom.php

"MYcustom" library uses a parameter array from a config file which lives in:
application/config/MYcustom.php

The library's constructor:
function MYcustom($params = array()){
$this->params = $params;
}

Reference to the library in a controller:
$this->load->library('MYcustom');
$this->mycustom->doSomething();

This set-up is working fine on MAMP.

But when everything is uploaded to my server, the library's parameters do not load.
I'm not seeing any other errors.