I removed the line export ........
and just wrote JBOSS_HOME=/path/NEW/jboss-5.1.0.GA
again here is same problem.
setting of JBOSS_HOME is not necessary.
your problem looks like a collision with another JBOss instance or other program.
In the server.log I found a line 'Port 8083 already in use'.
Are you sure no other JBoss instance is running?
Also look at the first ERROR message in the log file, and follow the 'caused by' links - the last 'caused by' willtell you what the problem is:
Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: org.jboss.seam.transaction.EjbSynchronizations
Looks like a Seam JAR file is missing.