As it is a component, you can set it up into any xml extension file in your OSGI-INF folder, if you use Nuxeo IDE, or directly in an xml extension if you use Nuxeo Studio (more information). Third solution is to name you xml file with whatever_your_want-config.xml (only the -config.xml part is important), and put it in the config directory of your server:

• $NUXEO/nxserver/config for a Tomcat distribution,
• $NUXEO/server/default/deploy/nuxeo.ear/config for a JBoss distribution.

Also, if you use the first option, don't forget to declare the xml extension file in your MANIFEST.MF in your META-INF folder.