That's quite strange... that is, in fact, the error you should have been receiving *before* using this latest snapshot version, but it should be working right now. I've just tested a modification of the "sayhello" example application with a "sayToPlanet" attribute and it works perfectly...
Could you please tell me the value that is being output for your attribute at configuration start time and also paste your "getAttributeApplicabilities()" method for that attribute processor?
With "value being output for your attribute at configuration start time" I mean the log line (in DEBUG mode) being output like:
Btw, I've uploaded a new snapshot. It doesn't change anything regarding this topic, but if you want to make sure you are using the latest 1.0.0-beta5 snapshot you can set your dependency to version "1.0.0-SNAPSHOT" instead of the specific version of the snapshot. This will make maven always check the latest version.
I've tested it with the following snapshots
(and I double-checked these are the versions in my classpath), and it works perfectly, so I think I had a .jar cache issue.
By the way, I mistakenly said "version 1.0.0-SNAPSHOT" in my last message when I meant "1.0.0-beta5-SNAPSHOT". That is the version value you have to use to make sure Maven is always using the latest snapshot of the future beta5.