Ronen,
I’m afraid this problem is not easy to track down remotely. To help narrow down the problem, can you help us find obvious differences between the two EARs exported?
a) I assume the file sizes are different.
b) If you expand each of the EARs (8.5 and greater) into separate folders do you find that the size of the EJB jars within are different? Are there other differences?
c) If yes, can you further expand the EJB jars and find which particular folders are missing or different in the two versions.
Instead of a manual investigation, you could alternatively unzip each EAR and subsequently unzip all JARs and WARs within that EAR into their respective folders. You can these use a diff tool like CSDiff to compare the two directories and generate a report that will help us take this further. Please ensure you unzip the component WAR and JAR files into the same locations within each EAR to get an accurate diff report.