I succeed to make it work and I don't know how.
In fact, I named the directory META-INF in minuscule instead of capital letter. When I renamed it with capital letters, it has worked.
It's a strange behaviour
It's not "strange behaviour", it's the spec.
How on earth could renaming the META-INF directory follow the spec?
I am having the same problem with the EAR not deploying the SAR's it contains on 4.0.2.
Tried everything, and if I have to go to the point of renaming the META-INF directory everytime I would rather switch app servers.
Because the spec says the folder is to be called 'META-INF', if you use lower case that is effectively a different folder name.