When calling an EJB from another EJB should they both be packaged in same JAR?. Are the any preferences for Weblogic or any other servers?

Alexey Ryndin

Definitely not. You can use any object published in JNDI by looking up it by name, obtain reference to it and narrowing this reference. As far as I know this can be done with any J2EE compatible server.

The only possible catch is to have the client classes available to the calling bean. See What classes does a client application need to access EJB?