Simulation Speed when using Xilinx DCM

Is there any way to speed up simulation (functional or timing) when simulating a Xilinx FPGA which uses the DCM? The DCM requires that the simulator resolution be set to ps range and this really slows down the simulation speed. I have reduced time delays in my design to reduce the simulation time required, however it still takes about 1 hour per millisecond of simulation time. Other than getting a faster computer are there any other things that can be done to reduce the simulation time? I have already removed high frequency signals (clocks) from the simulator waveform window and used variables where possible.