Simulator to PowerPlay Power Analyzer WARNING

For a very simply design (basically a multiplier) I obtain this Warning in Simulator Messages:

Cannot find channels in vector source file for the following output ports - channels

are required for VCD file generation for PowerPlay Power Analyzer

and the number of output ports is really huge!! almost all the intermediate signals are listed.

I try to eliminate this Warning by different ways, but it was impossible; and I don't know how this affect the PowerPlay power estimation.