Bukkit

1. What steps will reproduce the problem ?

I have a recipe to craft a specific item with @name and @lore, then I have a smelting recipe to smelt that specific item with specific fuel.  If you shift-click the ingredients into the furnace, it will only let you put in the item with the specific name and lore.  If you drag the base item without NBT into the furnace after shift clicking the fuel in, it will smelt the base item into the recipe material.  It does this randomly and sometimes not at all. I was able to replicate it after placing about 10 furnaces and trying it in each one.  Not every furnace appears to do it.

It also did this in version 2.3.2, and was fixed in 2.3.3 but seems to have reverted back, partially.

To replicate, use the recipe file below and shift click a redstone block in the furnace and put in the "Diamerald Block" that is crafted and immediately remove it, then drag a vanilla diamond block and it will smelt it into a sea lantern.  If you shift click the diamond block in, it will tell you it needs to be specific lore and name.

Recipe file:

FUEL
redstone_block % 80

CRAFT Diamerald Block
diamond + diamond + diamond
diamond + emerald + diamond
diamond + diamond + diamond
= diamond_block
  @name &bDiam&aerald <white>Block
  @lore &6It's so beautiful.

SMELT Sea Lantern
@ingredientcondition diamond_block | name &bDiam&aerald <white>Block | lore &6It's so beautiful.
diamond_block
& redstone_block
= sea_lantern
  @name &3Sea Lantern

2. Do you have an error log of what happened ?
(NOTE: RecipeManager also prints other kind of errors regarding recipe parsing, you should consider those too)

N/A

3. What is the expected output ? What do you see instead ?

Should only be allowed to smelt diamond block with specific NBT name and lore, but can smelt a regular block of diamond if you drag it into the slot.

4. What version of RecipeManager and CraftBukkit are you using ?
(NOTE: If you're not using the latest version of any of those, re-test using the latest versions)

RM 2.3.4 and Spigot 1.8.1

5. Did you use "rmreload" or "reload" commands in that server session ? If so, specify which.

No.

I think I've found a fix for this, but it's not perfect so I'll probably be looking into either rewriting some of the furnace handling or at least improve it a little more until I have the time to rewrite it.