Working in Civil 3D 2011, layers which are frozen in a Layout tab view port still display and still plot. This appears to apply to entities in the current drawing, referenced drawings and referenced images. The only way to prevent the layer from plotting in the Layout tab is to freeze it in Model Space, or make the layer "no plot". Anything on the frozen layer cannot be selected within the view port, but still displays and plots. Within the view port, LAYFRZ command freezes the layer in model space, but still shows as thawed in the VP Freeze column in the Layer Properties Manager. It always used to be the other way around. The display and plot problem may be limited to random drawings, not necessarily all. Help?