How to point data-source-aliases.xml to another Datasource

Hello,

I've created an CMP EJB.

I would like to create a Datasource alias for a Datasource I have on the Web AS.

When creating data-source-aliases.xml it creates the alias by default on ${com.sap.datasource.default} which is the default DB.

What should instead in case I want to create an alias on my Datasource called EVAL on the WAS?