Default namespaces are registered by repository at the start-up time

Your custom service can extend a set of namespaces with some application specific ones, declaring it in service's configuration file thanks to eXo component plugin mechanism, described as follows:

      <component-plugin> 

          <name>add.namespaces</name>

          <set-method>addPlugin</set-method>

          <type>org.exoplatform.services.jcr.impl.AddNamespacesPlugin</type>

          <init-params>

            <properties-param>

              <name>namespaces</name>

              <property name="test" value="http://www.test.org/test"/>

            </properties-param>      

          </init-params>                  

      </component-plugin>