if there is something with the same name and we do not support SNS, we would need the exception yes. otherwise never (f.e. if internally uuid are assigned even for not referenceable nodes - then a new uuid would have to be created. but i think jackrabbit handles that for us, right?)

the thing about forward compatible is that if SNS are allowed, this test is completely wrong as no exception is to be assumed. lets check the capability and mark the test skipped if SNS are supported, saying that this needs to be done with an implementation that actually supports SNS. doing the test that is never run would be weird...