It's actually in .55, but apparently we cannot select that as the product version :)
I tried making five fireplaces, and every single one of them despawned instantly or within seconds of crafting. The ones that instantly despawned came from when I had items in my hands - those that lasted three seconds were when I had nothing in my hands. I tried five different times on the same server, with the same result. This is game breaking, so it needs to be fixed ASAP.