Thank you. This is a bug, so I have created new issue [JBIDE-15625] Faces-config validation wrongly reports a warning for two renderers with the same renderer-type - JBoss I… with reference to this post.
Is it possible to workaround it (however lame it may be) by splitting the default renderer kit between two faces configs, one renderer in each, both configs registered in web.xml? Validation is restricted to a file.
Splitting problematic renderers into separate faces-configs works.
As you said, its pretty lame solution and i cannot say its workaround, because its just a problem in one IDE and one plugin in this IDE. That cannot be a reason for splitting files. Other developers with different IDE/plugin on the same project would agree.
Anyway thanks for creating new issue, hope it will be fixed soon.
Fixed in 4.1.1.Beta1