VERY technical bug

Today i've seen that the name of double slabs was double_stone_slab
I knew in 1.4.2 it was possible to give you a slab with ID 43:8 or 43:9,43 being the ID of double slabs

Then i did a /setblock,and then,it says:There is no such item with name minecraft:double_stone_slab.
I pressed F3 on my example of double slabs,i wrote really minecraft:double_stone slab.

An attached text file and .png file is under

Please correct this bug and fix your game mojang