Enhancing OpenJPA entity in runtime in jboss - jpa

Question

I am not able to run my spring mvc+openjpa applicaton on jboss AS 7.1.x in my windows laptop.
After deployment when i execute it, it says -
org.apache.openjpa.persistence.ArgumentException: Attempt to cast instance "com.caobusiness.selfcare.entity.DummyTable#1698b9" to PersistenceCapable failed. Ensure that it has been enhanced.
After searching, i found that open jpa entities needs to be enhanced either during built time or run time. I am trying to enhance entity during runtime using javaagent, but it fails.
my jboss standalone.conf looks like
#
# Specify options to pass to the Java VM.
#
if [ "x$JAVA_OPTS" = "x" ]; then
JAVA_OPTS="-Xms64m -Xmx512m -XX:MaxPermSize=256m -Djava.net.preferIPv4Stack=true -Dorg.jboss.resolver.warning=true -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000"
JAVA_OPTS="$JAVA_OPTS -Djboss.modules.system.pkgs=$JBOSS_MODULES_SYSTEM_PKGS -Djava.awt.headless=true"
JAVA_OPTS="$JAVA_OPTS -Djboss.server.default.config=standalone.xml"
JAVA_OPTS="$JAVA_OPTS -javaagent:D:\openjpa-2.2.0.jar"
else
echo "JAVA_OPTS already set in environment; overriding default settings with values: $JAVA_OPTS"
fi
I do not want to go for built time enhancement as of now. I have gone through posts stackoverflow post and why enhancement is needed
Will appreciate some leads.