problem resetting world !

[14:29:55 INFO]: [SurvivalGames] [SG] The Survival Games are restarting...
[14:29:55 INFO]: [SurvivalGames] Unloading world 'Survival Games'... (world)
[14:29:55 INFO]: [SurvivalGames]     Unloading chunks...
[14:29:56 INFO]: [SurvivalGames]     442 chunks unloaded.
[14:29:57 INFO]: [SurvivalGames] World 'Survival Games' unloaded. (world)
[14:29:57 INFO]: [SurvivalGames]     Extracting world zip 'world.zip'...
[14:29:57 INFO]: [SurvivalGames]         Existing world folder deleted.
[14:29:57 INFO]: [SurvivalGames] Unable to unzip world zip! (world.zip)
[14:29:57 WARN]: net.lingala.zip4j.exception.ZipException: Probably not a zip fi
le or a corrupted zip file
[14:29:57 WARN]:        at net.lingala.zip4j.core.HeaderReader.readEndOfCentralD
irectoryRecord(HeaderReader.java:179)
[14:29:57 WARN]:        at net.lingala.zip4j.core.HeaderReader.readAllHeaders(He
aderReader.java:78)
[14:29:57 WARN]:        at net.lingala.zip4j.core.ZipFile.readZipInfo(ZipFile.ja
va:425)
[14:29:57 WARN]:        at net.lingala.zip4j.core.ZipFile.extractAll(ZipFile.jav
a:475)
[14:29:57 WARN]:        at net.lingala.zip4j.core.ZipFile.extractAll(ZipFile.jav
a:451)
[14:29:57 WARN]:        at net.shockverse.survivalgames.ArenaManager.extractWorl
dZips(ArenaManager.java:1164)
[14:29:57 WARN]:        at net.shockverse.survivalgames.ArenaManager$2$1$1.run(A
renaManager.java:953)
[14:29:57 WARN]:        at net.shockverse.survivalgames.extras.GameTask$1.run(Ga
meTask.java:55)
[14:29:57 WARN]:        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftTask.ru
n(CraftTask.java:58)
[14:29:57 WARN]:        at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftSchedul
er.mainThreadHeartbeat(CraftScheduler.java:345)
[14:29:57 WARN]:        at net.minecraft.server.v1_7_R1.MinecraftServer.u(Minecr
aftServer.java:583)
[14:29:57 WARN]:        at net.minecraft.server.v1_7_R1.DedicatedServer.u(Dedica
tedServer.java:259)
[14:29:57 WARN]:        at net.minecraft.server.v1_7_R1.MinecraftServer.t(Minecr
aftServer.java:540)
[14:29:57 WARN]:        at net.minecraft.server.v1_7_R1.MinecraftServer.run(Mine
craftServer.java:446)
[14:29:57 WARN]:        at net.minecraft.server.v1_7_R1.ThreadServerApplication.
run(SourceFile:617)
[14:29:57 WARN]: Caused by: java.io.IOException: Negative seek offset
[14:29:57 WARN]:        at java.io.RandomAccessFile.seek(Native Method)
[14:29:57 WARN]:        at net.lingala.zip4j.core.HeaderReader.readEndOfCentralD
irectoryRecord(HeaderReader.java:117)
[14:29:57 WARN]:        ... 14 more