Sign

When i am going to setblock sign i does not work. I tryed writing it diffrent. I tryed testforeblock air, and it says: The Block at -1410,53,1213 is Sign (expectted:tile.air.name). After that i tryed testforblock Sign and it says: There is no such Block With ID/name Sign. I also tryed writing sign...? So is this a bug or is it no name for sign.