After server start-up you login to http://localhost:8080/jboss-brms which asks you if you want to install the sample repository in your new system. When I said yes, it would run a bit and then give me an error like this:
22:05:00,094 ERROR [STDERR] Exception in thread "http-127.0.0.1-8080-5" 22:05:00,094 ERROR [STDERR] java.lang.OutOfMemoryError: PermGen space 22:05:00,152 ERROR [ContainerBase] Servlet.service() for servlet guvnorService threw exception java.lang.OutOfMemoryError: PermGen space at java.lang.Throwable.getStackTraceElement(Native Method) etc.........
To fix this you need to tweak the jboss-as/bin/run.sh by adding near the top of the file the following line:
# Set a sane PermSize. JAVA_OPTS="$JAVA_OPTS -XX:MaxPermSize=256m"
Restart EAP 4.3 and the installation of your sample repository will run fine.