/Gamemode 2 @a triggered with command block doesn't work

ALSO /gamemode 1 @a doesn't work
Can break blocks and fly; BUT GHOST MODE
can't fly/walk through blocks

I am guessing the @a selector fails to execute the whole command

NO ANVILDAMAGE IN GAMEMODE 2

---- Minecraft Crash Report ----

Time: 24.01.14 21:31
Description: Manually triggered debug crash

java.lang.Throwable
	at bby.p(SourceFile:1437)
	at bby.aj(SourceFile:774)
	at bby.f(SourceFile:728)
	at net.minecraft.client.main.Main.main(SourceFile:154)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
	at bmw.a(SourceFile:298)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [boy['maxtheking'/10, l='MpServer', x=1508,30, y=57,62, z=-549,70]]
	Chunk stats: MultiplayerChunkCache: 121, 121
	Level seed: 0
	Level generator: ID 01 - flat, ver 0. Features enabled: false
	Level generator options: 
	Level spawn location: 1513,00,56,00,-531,00 - World: (1513,56,-531), Chunk: (at 9,3,13 in 94,-34; contains blocks 1504,0,-544 to 1519,255,-529), Region: (2,-2; contains chunks 64,-64 to 95,-33, blocks 1024,0,-1024 to 1535,255,-513)
	Level time: 1646424 game time, 6000 day time
	Level dimension: 0
	Level storage version: 0x00000 - Unknown?
	Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
	Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
	Forced entities: 10 total; [yw['Villager'/0, l='MpServer', x=1518,17, y=60,83, z=-572,50], yw['Villager'/1, l='MpServer', x=1514,50, y=61,00, z=-570,50], boy['maxtheking'/10, l='MpServer', x=1511,44, y=59,62, z=-549,70], xi['Falling Block'/7399, l='MpServer', x=1509,50, y=108,15, z=-548,50], xi['Falling Block'/7395, l='MpServer', x=1508,50, y=105,35, z=-546,50], xi['Falling Block'/7376, l='MpServer', x=1509,50, y=63,60, z=-548,50], boy['maxtheking'/10, l='MpServer', x=1508,30, y=57,62, z=-549,70], boy['maxtheking'/10, l='MpServer', x=1513,01, y=57,62, z=-528,33], xi['Falling Block'/7426, l='MpServer', x=1508,50, y=141,96, z=-547,50], xi['Falling Block'/7430, l='MpServer', x=1511,50, y=143,71, z=-549,50]]
	Retry entities: 0 total; []
	Server brand: vanilla
	Server type: Integrated singleplayer server
Stacktrace:
	at bmw.a(SourceFile:298)
	at bby.b(SourceFile:2029)
	at bby.f(SourceFile:737)
	at net.minecraft.client.main.Main.main(SourceFile:154)

-- System Details --
Details:
	Minecraft Version: 14w04b
	Operating System: Windows 8 (amd64) version 6.2
	Java Version: 1.7.0_60-ea, Oracle Corporation
	Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
	Memory: 162827752 bytes (155 MB) / 323485696 bytes (308 MB) up to 954728448 bytes (910 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G
	IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
	Launched Version: 14w04b
	LWJGL: 2.9.1
	OpenGL: GeForce GT 750M/PCIe/SSE2 GL version 4.4.0, NVIDIA Corporation
	GL Caps: Using GL 1.3 multitexturing.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: []
	Current Language: English (UK)
	Profiler Position: N/A (disabled)
	Anisotropic Filtering: Off (1)

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