Rail Dissapears

When you piston (either piston) a rail (any type except normal rail) onto the top of a honey block, the rail disappears, it doesn't drop as an item and it doesn't show on the honey and isn't there, tested by trying to place minecart. Even if you break the honey block it doesn't drop. But, if you place a block after the honey with some rail (any type) on top and then piston the rail onto the honey block, the rail breaks and drops as an item.