Maybe I'm missing something (different definition), but the spherical harmonic function SphericalY gives wrong results. For example, SphericalY(0,0,0,0) evaluates to 0, but should be 1/(2*sqrt(Pi)) (see e.g. http://en.wikipedia.org/wiki/Spherical_harmonic, also Mathematica gives this answer). Note that there is no possibility for arguments mismatch in this case. Do you have any explanation? (I'm using Maple 10.)