Calculations on systems with were made. For the fixed boundary condition used, the lowest frequency mode is the mode which becomes soft at some . On the other hand, when free boundary conditions are used, there are also a few modes that can lie below the soft mode, reflecting the greater freedom of movement of the boundary spins; the lowest mode is at corresponding to a uniform rotation of all the spins in the easy-plane, a motion that is frozen out by the fixed boundary condition.