This is an FAQ :-)
I'll bet you're trying to use CMR and your CMR attribute has a <cmp-field> element in your ejb-jar.xml file?
Don't do that.
My code deploys and works fine on weblogic so if its an cmr with a cmp-field as the same name would this still deploy.....
It's my understanding of the spec that you have one or the other. Check out section 10.3.1.
If this is indeed what you have done, then it may be a weblogic extension (or bug).