I use commandblock to execute the command , but it crash.
In 14w21b , it still works.
Here is my command.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {EntityId:FallingSand,SpawnData:{Block:"minecraft:redstone_block",Time:1,DropItem:0}}

I am very upset for this , and I wish Mojang could fix it soon.
Sorry for bad English , I am a Taiwanese Minecrafter and lover.

End to say , thank you for reading this issue.