I just upgraded to Maple 12 because of its ability to perform abstract index calculations. However, I'm having trouble getting started with it. My first problem is with the Simplify command: if I define a completely symmetric tensor using the command

Define(T,symmetric);

and an antisymmetric tensor using the command

Define(w,antisymmetric);

then

Simplify(T[mu,nu,rho]*w[mu,nu]);

correctly returns 0. However, if I define T to be symmetric in only its first two indices,

Define(T[mu,nu,rho],symmetric={mu,nu});