I had built a C++ worker with a typo in the spec file name and had a hard time tracking down this problem.
the name other spec was wrong but the name of the file was right and the same as the name in the implementation. trying to run the application I got errors about not being able to find an implementation for my C++ worker even though i thought i had pointed the tools to the .so for this worker. turns out there was a typo in my spec file, this was a hard error to track down with the existing debug messages.
a better way to debug this type of error would be great.