I found the description of the xmlbeans 5 maven plugin configuration. It tells to add the dependency on log4j-core of the schema generation to the configuration.
However, it seems not to work. I still get the error message
SchemaCompiler Metadata LOAD:org/apache/xmlbeans/metadata GEN:eu/ngong/eaGuid
ERROR StatusLogger Log4j2 could not find a logging implementation. Please add log4j-core to the classpath. Using SimpleLogger to log to the console...
Obviously the SchemaCompiler needs log4j-core while generating. Is there another way to put log4j-core onto the classpath while generating?
The related question helped me.
I had to add the dependency in pom.xml directly in the plugin clause: