from your log it seems like you have problem with your database connection (h2), if you want to run with this default database, you have to start it with command:
java -cp gatein-node1/modules/com/h2database/h2/main/h2-1.3.168.jar org.h2.tools.Server
as described at https://github.com/gatein/gatein-portal/tree/master/packaging/jboss-as7 (README - Clustered mode part)
Or you can try with some production databaze which you plan to use.
Feel free to ask if you will hit some other issues.
Ah, totally missed that document. Thanks. Am I reading it right that clustering support is limited to 7.1.3.Final?
" ...'cluster' build profile available for JBoss AS 7.1.3.Final packaging."