I'm experiencing a similar issue as well, any additional advice would be appreciated. I run just a tiny personal server for family and friends, so I have plenty of opportunity to test or troubleshoot if someone wants to work with me to figure this out. If there is any additional information I can provide please let me know. Oh and apologies in advance for the wall of text.
Server running: CraftBukkit version git-Bukkit-jenkins-CraftBukkit-173 (MC: 1.2.5) (Implementing API version 1.2.5-R4.1-MCPC-SNAPSHOT)
Plugins (58): mod_WirelessRedstoneAddons, mod_BuildCraftEnergy, mod_RedPowerWiring, GroupManager, mod_BuildCraftCore, mod_ImmibisCore, Multiverse-Core, mod_BuildCraftFactory, mod_NetherOres, TreeAssist, mod_EE, MagicSpells, mod_TubeStuff, Permissions, mod_CCTurtle, mod_IC2NuclearControl, mod_WirelessRed
stoneRedPower, mod_ccSensors, mod_ImmiChunkLoaders, mod_CompactSolars, mod_WirelessRedstoneCore, mod_IC2_ChargingBench, mod_IronChest, mod_MinecraftForge, WorldEdit, EnchantView, Multiverse-Inventories, mod_RedPowerControl, Multiverse-NetherPortals, mod_IC2, mod_RedPowerMachine, mod_BuildCraftBuilders, mod_RedPowerLighting, mod_RedPowerWorld, mod_ComputerCraft, mod_BuildCraftTransport, mod_NotEnou
ghItems, CraftBookCommon, mod_PowerConverters, CommandHelper, mod_AdditionalPipes, mod_IC2AdvancedMachines, mod_Railcraft, mod_RedPowerCore, Runecraft, mod_RedPowerLogic, mod_ModularForceFieldSystem, mod_EnderStorage, mod_CodeChickenCore, Balkon's WeaponMod, Essentials, CraftBookMechanisms, Multiverse-Portals, CommandBook, EssentialsChat, CraftBookCircuits, EssentialsSpawn, CraftBookVehicles
I have taken the following troubleshooting steps:
Stop the server
Remove all - tablet_(playername).dat files, across all worlds.
Restart server
Login (localhost), recreate tablet from a crafting table and place it
Access the tablet, 0 EMC, No Lock
Note: I was watching the ..\server\worldname\data\ folder on a separate screen to see when the tablet_playername.dat file is created. Which happens to be the first time you access the tablet in game.
Here are my in game test steps and observations:
Drop a cobble, stone, dirt, sand, netherrack, obsidian, etc in the left slots, no change or effect.
Drop the same items in the 'burn' slot and I notice a single "Learned" indicator for the first item, then nothing for the next.
Also the right display doesn't reflect any added items until i go out of the tablet screen and back in.
[*]Remove all items back down to 0 EMC.
[*]Spawn an Alchemical Tome and drop it in the burn slot, no "Learned" indication or change.
[*]Leave and go back into the Tablet, no change or indication (all slots are blank 0 EMC).
[*]Drop some items into the burn slot to add EMC, the EMC numbers increase but there are no items displayed to match
[*]Leave and go back into the tablet, many items are now displayed
Note: When I pull a single cobble from the right panel the item is 'removed' and I can't select another one with the remaining EMC, but I am able to Shift-Click a different block to produce a small stack using the remaining EMC and that item still shows on the right panel as an option.
[*]Placing items/blocks in the center of the right panel does not change the display of items
Leaving the item/block in the center-right drops the item out if you leave the Tablet view, also the same for the left panel slots, all 'unburned' items are dropped when leaving the tablet view.
[*]Also, the tablet will allow me to take an item causing a Negative EMC value to remain.
[*]Lastly I can't seem to unlock from matter or fuel once I have placed one or the other in the tablet.
I'm going to next try the suggestion to downgrade my EE version as described above and report back on my findings. I hope I can help to resolve this conflict. Thanks!