Java: important BackgroundSubtractionMOG2 parameters cannot be set (Bug #3573)

After instantiating a BackgroundSubtractionMOG2, via parent class Algorithm we are able to getDouble() the parameters fTau and nShadowDetection, but setting does nothing for the fTau and creates the following error for nShadowDetection;

OpenCV Error: Bad argument (Argument error: the setter method was called for the parameter 'nShadowDetection' of the algorithm 'BackgroundSubtractor.MOG2', the parameter has unsigned char type, so it should be set by integer, unsigned integer, uint64, unsigned char, boolean, float or double value, but the setter was called with double value) in set, file /home/will/opencv-2.4.8/modules/core/src/algorithm.cpp, line 654

For example, the following code;

BSMOG2 = new BackgroundSubtractorMOG2(2, 16, true);

  double x = BSMOG2.getDouble("fTau");

  System.out.println("BSMOG2.getDouble(fTau) = " + x);

  double yy = BSMOG2.getDouble("nShadowDetection");

  System.out.println("BSMOG2.getDouble(nShadowDetection) = " + yy);

and the output is;

_BSMOG2.getDouble(fTau) = 0.5

BSMOG2.getDouble(nShadowDetection) = 127.0_

to set the values, I did;

BSMOG2.setDouble("fTau", 0.7);

EDIT: This executes without warning or complaint, but never really sets fTau, the value continues to be 0.5

And setDouble for nShadowDetection crashes with the following very odd statement;

OpenCV Error: Bad argument (Argument error: the setter method was called for the parameter 'nShadowDetection' of the algorithm 'BackgroundSubtractor.MOG2', the parameter has unsigned char type, so it should be set by integer, unsigned integer, uint64, unsigned char, boolean, float or double value, but the setter was called with double value) in set, file /home/will/opencv-2.4.8/modules/core/src/algorithm.cpp, line 654

On top of that, I tried other operations (paramType) to see what they resulted in;

Paramtype for fTau is 7
Paramtype for nShadowDetection is 11

I can't figure out what these mean.

I also tried String paramhelpfTau = BSMOG2.paramHelp("fTau");

But that was null.

The BackgroundSubtractionMOG2 is virtually unusable if one cannot change the parameters.