Security exception with jbpm jars

[learnkey]

Hi,

     I am getting the following security exception while using jbpm BRMS_5.3 jars with jboss 7.0.2 server.

java.lang.SecurityException: class "org.jbpm.task.SubTasksStrategy$$EnhancerByCGLIB$$8799bff0"'s signer information does not match signer information of other classes in the same package

java.lang.SecurityException: class "org.jbpm.process.audit.NodeInstanceLog$$EnhancerByCGLIB$$63f3ef3"'s signer information does not match signer information of other classes in the same package

Any pointers to this issue is appreciated.

Thanks in advance