Continus Server Error

[Addaption]

I keep getting this error please anyone help
06:45:11 [SEVERE] at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:951)
06:45:11 [SEVERE] at ho.r(DedicatedServer.java:309)
06:45:11 [SEVERE] at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:857)
06:45:11 [SEVERE] at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:744)
06:45:11 [SEVERE] at fy.run(ThreadMinecraftServer.java:16)
06:45:11 [SEVERE] Caused by: java.lang.NoClassDefFoundError: yd
06:45:11 [SEVERE] at yc.m(World.java:1119)
06:45:11 [SEVERE] at yc.h(World.java:1065)
06:45:11 [SEVERE] at yc.f(World.java:1009)
06:45:11 [SEVERE] at yc.e(World.java:967)
06:45:11 [SEVERE] at aje.c(BlockFlower.java:71)
06:45:11 [SEVERE] at aje.b(BlockFlower.java:63)
06:45:11 [SEVERE] at ama.b(BlockSapling.java:45)
06:45:11 [SEVERE] at in.g(WorldServer.java:603)
06:45:11 [SEVERE] at in.b(WorldServer.java:312)
06:45:11 [SEVERE] at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:945)
06:45:11 [SEVERE] ... 4 more
06:45:11 [SEVERE] Encountered an unexpected exception t
t: Exception ticking world
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:951)
at ho.r(DedicatedServer.java:309)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:857)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:744)
at fy.run(ThreadMinecraftServer.java:16)
Caused by: java.lang.NoClassDefFoundError: yd
at yc.m(World.java:1119)
at yc.h(World.java:1065)
at yc.f(World.java:1009)
at yc.e(World.java:967)
at aje.c(BlockFlower.java:71)
at aje.b(BlockFlower.java:63)
at ama.b(BlockSapling.java:45)
at in.g(WorldServer.java:603)
at in.b(WorldServer.java:312)
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:945)
... 4 more
06:45:11 [SEVERE] This crash report has been saved to: /server/./crash-reports/crash-2013-04-28_06.45.11-server.txt

 

[Booker The Geek]

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