I am using a POJO (Non-EJB) class inside my JBoss server and creating multiple instances of it. Will JBoss create an object pool and manage this resource or will it simple create as many objects as I instantiate ?
Plain Old Java Objects are "unmanaged" the container has no way to know that when you say "new" you don't really mean "new".
EJBs have managed life cycles, are trivial to implement. If you want pooling why not use one?