strange bug in quantity.Symbolic -> valueContinuous after concatenation

See unittest: quantity.testSymbolic/testValueContinuousBug I don't understand yet, why the following unittest does not work. Probably valueContinuous is ordered falsely after concatenation. As B2(1).valueContinuous is somehow ordered differently compared to B2(2:4).valueContinuous or all B(:).valueContinuous, i.e. B2(1).valueContinuous is (zeta, z) instead of (z, zeta).

Here the related code of the unsuccessful unittest:

function testValueContinuousBug(tc)

z = quantity.Domain("z", linspace(0, 1, 7));

zeta = quantity.Domain("zeta", linspace(0, 1, 5));

A = quantity.Symbolic(sin(sym("z") * pi), z);

B = [0*z.Symbolic + zeta.Symbolic, A + 0*zeta.Symbolic; z.Symbolic+zeta.Symbolic, A * subs(A, "z", "zeta")];

B2 = [zeta.Symbolic + 0*z.Symbolic, A + 0*zeta.Symbolic; z.Symbolic+zeta.Symbolic, A * subs(A, "z", "zeta")];

tc.verifyEqual(B.on([z, zeta]), B2.on([z, zeta]));

end % testValueContinuousBug()