For anyone who reach this link too late:
You get error since it is using up too much memory while starting up. You can control the memory that it used in the file run.conf under the bin directory of jboss. Open run.conf and search for 'mem' and you will see the line where you can set the memory which will used for the heap. It was 256 and 512 for mine and i changed to 128 and 256 and it worked fine.