Jars amp getResource

Hello

I have problem with resources.
My code look like this:

Url url = MyClass.class.getResource(“config.xml”);
or
Url url = this.getClass().getResource(“config.xml”);

This code works when I run it from console, but in WM IS don’t.
I get null.

Can you help me? How can I get access to resource in jar files?

Thank you,
Patryk