Thank you very much for your advice and time!
I think I have found the problem. I didn't declare resource-ref or added the annotation resource. However, if I have to have this declared and don't have this entry I will get an error. I was definitely hoping for a solution where I had a default behaviour and if someone added this resource it would override the default behaviour. If the lookup is only done in code I can use a try catch to handle this but that doesn't seem possible for annotations or xml config files...
Well I guess I have to come up with something else...
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