Hey, I'm here...
I'm just telling you what worked for me.
From within the project root dir I execute the following command:
wscompile -verbose -classpath ./bin -gen:server -f:rpcliteral -mapping mapping.xml config.xml
where config.xml is in the project root dir;
where bin is the dir where Eclipse put the compiled classes and related packages (bin is a child of project root dir).
I think you are wrong in the dir name format.
Hope this works.