Multiple-spiral-wave solutions of the general cubic complex Ginzburg-Landau
equation in bounded domains are considered. We investigate the effect of the
boundaries on spiral motion under homogeneous Neumann boundary conditions, for
small values of the twist parameter q. We derive explicit laws of motion for
rectangular domains and we show that the motion of spirals becomes
exponentially slow when the twist parameter exceeds a critical value depending
on the size of the domain. The oscillation frequency of multiple-spiral
patterns is also analytically obtained