[Need Help starting my tekkit server]

I keep getting an error when I try to launch it. This is what happens.

C:\Users\Gary\Downloads\Tekkit Classic server>java -Xmx3G -Xms2G -jar Tekkit.jar

nogui

182 recipes

27 achievements

14:52:40 [iNFO] Starting minecraft server version 1.2.5

14:52:40 [iNFO] Attempting early MinecraftForge initialization

14:52:40 [iNFO] Completed early MinecraftForge initialization

14:52:40 [iNFO] Forge Mod Loader version 2.2.91.173 for Minecraft 1.2.5 loading

14:52:40 [iNFO] Loading mods from C:\Users\Gary\Downloads\Tekkit Classic server\

mods

14:52:40 [WARNING] Failed to load mod class net/minecraft/server/mod_NetherOres.

class in C:\Users\Gary\Downloads\Tekkit Classic server\mods\mod_NetherOres.jar

14:52:40 [sEVERE] Zip file mod_NetherOres.jar failed to read properly

14:52:40 [iNFO] File mod_NetherOres.jar contained no mods

14:52:40 [iNFO] Directory weaponmod contained no mods

14:52:40 [sEVERE] A problem has occured during mod loading. Likely a corrupt jar

is located in your mods directory

14:52:40 [sEVERE] cpw.mods.fml.common.LoaderException: cpw.mods.fml.common.Loade

rException: java.lang.UnsupportedClassVersionError: net/minecraft/server/mod_Net

herOres : Unsupported major.minor version 51.0

14:52:40 [sEVERE] at cpw.mods.fml.common.Loader.load(Loader.java:436)

14:52:40 [sEVERE] at cpw.mods.fml.common.Loader.loadMods(Loader.java:606)

14:52:40 [sEVERE] at cpw.mods.fml.server.FMLBukkitHandler.onPreLoad(FMLBuk

kitHandler.java:134)

14:52:40 [sEVERE] at net.minecraft.server.MinecraftServer.init(MinecraftSe

rver.java:135)

14:52:40 [sEVERE] at net.minecraft.server.MinecraftServer.run(MinecraftSer

ver.java:438)

14:52:40 [sEVERE] at net.minecraft.server.ThreadServerApplication.run(Sour

ceFile:492)

14:52:40 [sEVERE] Caused by: cpw.mods.fml.common.LoaderException: java.lang.Unsu

pportedClassVersionError: net/minecraft/server/mod_NetherOres : Unsupported majo

r.minor version 51.0

14:52:40 [sEVERE] at cpw.mods.fml.common.Loader.loadModClass(Loader.java:5

27)

14:52:40 [sEVERE] at cpw.mods.fml.common.Loader.attemptFileLoad(Loader.jav

a:562)

14:52:40 [sEVERE] at cpw.mods.fml.common.Loader.load(Loader.java:419)

14:52:40 [sEVERE] ... 5 more

14:52:40 [sEVERE] Caused by: java.lang.UnsupportedClassVersionError: net/minecra

ft/server/mod_NetherOres : Unsupported major.minor version 51.0

14:52:40 [sEVERE] at java.lang.ClassLoader.defineClass1(Native Method)

14:52:40 [sEVERE] at java.lang.ClassLoader.defineClassCond(Unknown Source)

14:52:40 [sEVERE] at java.lang.ClassLoader.defineClass(Unknown Source)

14:52:40 [sEVERE] at java.security.SecureClassLoader.defineClass(Unknown S

ource)

14:52:40 [sEVERE] at java.net.URLClassLoader.defineClass(Unknown Source)

14:52:40 [sEVERE] at java.net.URLClassLoader.access$000(Unknown Source)

14:52:40 [sEVERE] at java.net.URLClassLoader$1.run(Unknown Source)

14:52:40 [sEVERE] at java.security.AccessController.doPrivileged(Native Me

thod)

14:52:40 [sEVERE] at java.net.URLClassLoader.findClass(Unknown Source)

14:52:40 [sEVERE] at java.lang.ClassLoader.loadClass(Unknown Source)

14:52:40 [sEVERE] at sun.misc.Launcher$AppClassLoader.loadClass(Unknown So

urce)

14:52:40 [sEVERE] at java.lang.ClassLoader.loadClass(Unknown Source)

14:52:40 [sEVERE] at java.lang.ClassLoader.loadClass(Unknown Source)

14:52:40 [sEVERE] at java.lang.Class.forName0(Native Method)

14:52:40 [sEVERE] at java.lang.Class.forName(Unknown Source)

14:52:40 [sEVERE] at cpw.mods.fml.common.Loader.loadModClass(Loader.java:4

94)

14:52:40 [sEVERE] ... 7 more

14:52:40 [sEVERE] Unexpected exception

cpw.mods.fml.common.LoaderException: cpw.mods.fml.common.LoaderException: java.l

ang.UnsupportedClassVersionError: net/minecraft/server/mod_NetherOres : Unsuppor

ted major.minor version 51.0

at cpw.mods.fml.common.Loader.load(Loader.java:436)

at cpw.mods.fml.common.Loader.loadMods(Loader.java:606)

at cpw.mods.fml.server.FMLBukkitHandler.onPreLoad(FMLBukkitHandler.java:

134)

at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:135)

at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:438)

at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)

Caused by: cpw.mods.fml.common.LoaderException: java.lang.UnsupportedClassVersio

nError: net/minecraft/server/mod_NetherOres : Unsupported major.minor version 51

.0

at cpw.mods.fml.common.Loader.loadModClass(Loader.java:527)

at cpw.mods.fml.common.Loader.attemptFileLoad(Loader.java:562)

at cpw.mods.fml.common.Loader.load(Loader.java:419)

... 5 more

Caused by: java.lang.UnsupportedClassVersionError: net/minecraft/server/mod_Neth

erOres : Unsupported major.minor version 51.0

at java.lang.ClassLoader.defineClass1(Native Method)

at java.lang.ClassLoader.defineClassCond(Unknown Source)

at java.lang.ClassLoader.defineClass(Unknown Source)

at java.security.SecureClassLoader.defineClass(Unknown Source)

at java.net.URLClassLoader.defineClass(Unknown Source)

at java.net.URLClassLoader.access$000(Unknown Source)

at java.net.URLClassLoader$1.run(Unknown Source)

at java.security.AccessController.doPrivileged(Native Method)

at java.net.URLClassLoader.findClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Unknown Source)

at cpw.mods.fml.common.Loader.loadModClass(Loader.java:494)

... 7 more

>And then it never moves.

Help please?