Having checked the application and related log files, we could not determine the precise cause of this error.
It may have occurred due to some momentary eclipse/java issue or perhaps a file name encoding issue resulting from a some specific o/s file system configuration (each package in the application is maintained as a package_name.trp file in the file system).
Our experience shows that packages can be named using any language supported by your operating system (and that usually includes Hebrew).
Please verify that Window -> Preferences ... -> Workspace -> Text file encoding is set to Other -> UTF-8. This is vital for cases where your project may be edited on a different machine which may be using a different OS or encoding.
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