Defining a Discrete Random Variable - Maple

Using the package with(Statistics) in maple:

I have some problems defining a discrete Random variable with (for example) the properties:

The only thing (somewhat useful) I found in the maple-help guide was: The "empirical distribution":

Y1:= RandomVariable(EmpiricalDistribution(Array([5,6])));

It does the desirable thing w.r.t. the following things:

Probability(Y1=5)=Probability(Y1=6)=1/2, and Mean(Y1)=5.5, but it's getting bothersome when asking for: Probability(Y1=4) for example.

It gives the output:" sample_tally3" instead of "0", wich is ofcourse desired.

Does anyone know how to define this Discrete Random Variable, the right way?