Can no longer craft enchantment table

I don't know when this happened but at some point, I can no longer craft an enchantment table. It acts like the recipe is incorrect.

I have isolated it down to a problem within my player DAT files under the world folder(s) but I have no idea what that problem is.

I initially thought it was a plugin or permission problem but even after removing all plugins and setting myself as OP, I still could not craft it. I even restored my earliest backup from a month ago and got the same results. I know at one point we were able to craft enchant tables but it has been a while since I last tried.

I setup a brand new server and was able to craft the enchant table. But when I copied over my world folders, the recipe stopped working.

Other recipes seem to work just fine, however, I have not tried each and every single recipe in the game.

Not sure how to resolve this problem. I'm baffled how the player DAT files affect what can be crafted.

Any insight would be appreciated.

Tried CraftBukkit 1.6.4-R2.0 and R1.0 on Java 1.7.0_45 (64-bit) on Windows 7 (64-bit) and Ubuntu Server 12.04.3 LTS (64-bit)

EDIT: Issue further isolated from the world files down to the player.dat files under the world folder.

Player file format

Using NBTExplorer, I found the following differences between DAT files that can craft the enchant table and those that cannot. Here are entries missing in the player's NBT records that cannot craft the table:

SpawnX: -211
SpawnY: 73
SpawnZ: 147
SpawnWorld: world

I do not know what caused the problem but as players complain about not being able to craft (no idea who is affected and not), I will just have to delete their DAT file and let it get re-created. From my searches, very few people have reported such a problem.

LHammonds