We assume that you have a clean Tomcat version of GateIn, in other words, we assume that you have already all the jar files of GateIn and their dependencies into tomcat/lib, you have all the war files of GateIn into tomcat/webapps and you have the realm name "exo-domain" defined into the file tomcat/conf/jaas.conf.
Add the file sample-ext.war from sample/extension/war/target/ to the tomcat/webapps directory. (See the purpose of this file in the JBoss section).
Add the folder starter from starter/war/target/ to the tomcat/webapps directory. (See the purpose of this file in the JBoss section).
Rename the directory (unzipped folder) starter to starter.war (for more details see the warning below)
Add the jar file exo.portal.sample.extension.config-X.Y.Z.jar from sample/extension/config/target/ to the tomcat/lib directory. (See the purpose of this file in the JBoss section).
Add the jar file exo.portal.sample.extension.jar-X.Y.Z.jar from sample/extension/jar/target/ to the tomcat/lib directory. (See the purpose of this file in the JBoss section).
This can only work if the starter.war is the last war file to be loaded, so don't hesitate to rename it if your war files are loaded following to the alphabetic order.