This configuration is invalid (but the part that checks it is the outstanding issue in JBCL). acme1 exports ales version 1 and scott version 1 acme2 exports ales version 2 and scott version 3 foo wants to import ales version 1 from acme1 and scott version 3 from acme2 Tthis will lead to incompatibilities between the versions in the linked classloaders. foo, acme1 and acme2 are in the same "classloading space" so they must agree on a common instance of the classes in the exported ales package. It should be failing at deployment time with an "conflicting package resolution" error for the ales package. If foo wants to use scott version 3 (provided by acme2) then it must also use ales version 2 to be consistent. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4150300#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...