  The conformal field equations are used to discuss the local existence of
spherically symmetric solutions to the Einstein-Yang-Mills system which behave
asymptotically like the anti-de Sitter spacetime. By using a gauge based on
conformally privileged curves we obtain a formulation of the problem in terms
of an initial boundary value problem on which a general class of maximally
dissipative boundary conditions can be discussed. The relation between these
boundary conditions and the notion of mass on asymptotically anti-de Sitter
spacetimes is analysed.
