Question: CDF of Binomial(2, 1/2) is wrong

with(Statistics):

CDF(Binomial(2, 1/2), x); # wrong
               piecewise(x < 0, 0, 2 <= x, 1, 1)

CDF(Binomial(2, p), x); # also wrong
     piecewise(x < 0, 0, 2 <= x, 1, p = 0, 1, p = 1, 0, 1)

Maple can actually generate PDFs for discrete distributions:

bpdf := unapply(PDF(Binomial(2, 1/2), x), x);
          x -> (1/4)*Dirac(x)+(1/2)*Dirac(x-1)+(1/4)*Dirac(x-2)

int(bpdf(t), t = -infinity .. x); # correct CDF
         (1/4)*Heaviside(x)+(1/2)*Heaviside(x-1)+(1/4)*Heaviside(x-2)

But then functions of random variables do not seem to work :

bdist := Distribution(PDF = bpdf, Support = -infinity .. infinity);

CDF(bdist, x); # OK
           piecewise(x < 0, 0, x = 0, undefined, x < 1, 1/4, x = 1, undefined, x < 2, 3/4, x = 2,
           undefined, 2 < x, 1)

CDF(add(RandomVariable(bdist), i = 1 .. 2), x); # indeterminate
          int((1/16)*Dirac(_t)^2+(1/4)*Dirac(0)*Dirac(_t-1)+(3/8)*Dirac(0)*Dirac(_t-2)+(1/4)*Dirac(0)*
          Dirac(_t-3)+(1/16)*Dirac(0)*Dirac(_t-4), _t = -infinity .. x)

It's a bit disappointing that Maple generates PDFs in terms of the delta function but doesn't support them properly, because that could be an easy and natural way to define mixed distributions.