Property file in EAR

I have a property file located in a 'resource' folder in my enterprise application. This file is used by several EJB and Web modules, that is why I put it into the EAR. The manifest files of these modules contain the name of the folder in the EAR where the property file is located ('resource'). However the property file can't be loaded by ClassLoader.getResource().
If I put the property file into a jar-file and include jar-file name into the maifest file, everything works fine. The application server is Websphere 5.1.
This approach is described here:
J2EE Class Loading Demystified
Can anybody make any suggestion on what I might be doing wrong?
Thank you.