Japanese "Anchor" overprints on PC

Members may be interested in the postcard shown here which shows the "use" of a BoP Airmail stamp, overprinted with the Japanese Anchor, on a postcard "cancelled" for use by the Japanese army in New Guinea. Recently (Oct 2004) offered on E Bay it purports to have been expertised and attracted several bids. PPS members will appreciate that this is a pure fabrication produced in Japan after the end of WW2.