I looked briefly at it and it seems the gcc bridge has some problems making sense of the Fortran code. I did not find any of the older versions of lubridate being more promising.
Are you willing to do some work to get this working? There are two options:
1. Create a renjin specific package of lubridate essentially replacing the fortran and/or c code that does not work.
2. Fix the gcc bridge so that it manages to convert the fortran/c code to byte code.
I am fine with either approach and would be happy help.
Best regards,
Per