True. But also adds a lot of complexity on top of an already very complex translation. But it's certainly something we'll look at in the future (together with supporting Cobol and Fortran).
But I heard there are C++ to C translators. I don't know how good they are and how the resulting code looks like. But if they're decent, you could do C++ -> C -> Java :)
On the C++ to C translators: The first actual C++ compiler was actually a trans-compiler to C (actually the language was still called cFront back then, but basically it's the first version of C++[0]).
So in that case, the C++ to C compiler was there before the first real C++ compiler which appeared some time later.
But I heard there are C++ to C translators. I don't know how good they are and how the resulting code looks like. But if they're decent, you could do C++ -> C -> Java :)