error from server

[axius27]

hi all,

i started a server 2 weeks ago but when i log on i get for following data from the console:

2013-04-02 21:41:20 [iNFO] User tas27 connecting with mods [OCS, MFReloaded|CompatSufficientBiomes, RedPowerWiring, OmniTools, BuildCraft|Transport, RedPowerCompat, AdvancedPowerManagement, WR-CBE|Core, MFReloaded|CompatIC2, RedPowerLogic, ThermalExpansion|Energy, WR-CBE|RedPower, EnderStorage, AdvancedMachines, MFReloaded|CompatPams, mmmPowersuits, IronChest, MFReloaded|CompatRP2, BuildCraft|Energy, ImmibisCore, EE3, LogisticsPipes|Main, DimensionalDoors, ChickenChunks, factorization, RedPowerLighting, AppliedEnergistics, mod_bspkrsCore, RedPowerBase, MFReloaded|CompatExtraBiomes, MFReloaded, ThermalExpansion, NetherOres, BuildCraft|Silicon, weaponmod, APUnofficial, ThermalExpansion|Transport, BuildCraft|Core, IC2NuclearControl, ThermalExpansion|Factory, CompactSolars, DimensionalAnchors, MFReloaded|CompatForestry, IC2, StevesCarts, Mystcraft, WR-CBE|Addons, ComputerCraft, TreeCapitator, BuildCraft|Factory, RedPowerMachine, RedPowerCore, MFReloaded|CompatThaumcraft, AdvancedRepulsionSystems, CCTurtle, Tubestuff, RedPowerControl, MFReloaded|CompatTwilightForest, MFReloaded|CompatSoulShards, MFReloaded|CompatVanilla, BuildCraft|Builders, RedPowerWorld, MFReloaded|CompatXyCraft, PowerConverters]

2013-04-02 21:41:20 [iNFO] tas27[/58.96.43.162:53524] logged in with entity id 7178 at (21.034681958376183, 76.0, 161.07264561262235)

2013-04-02 21:41:20 [sEVERE] Encountered an unexpected exception NoClassDefFoundError

java.lang.NoClassDefFoundError: l

at a.<init>(CrashReport.java:27)

at a.a(CrashReport.java:319)

at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:673)

at ho.r(DedicatedServer.java:269)

at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:599)

at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)

at fy.run(SourceFile:849)

2013-04-02 21:41:20 [iNFO] Stopping server

2013-04-02 21:41:20 [iNFO] Saving players

2013-04-02 21:41:20 [iNFO] Saving worlds

2013-04-02 21:41:20 [iNFO] Saving chunks for level 'world'/Overworld

2013-04-02 21:41:21 [iNFO] Saving chunks for level 'world'/Nether

2013-04-02 21:41:21 [iNFO] Saving chunks for level 'world'/The End

2013-04-02 21:41:21 [iNFO] Saving chunks for level 'world'/Limbo

plz help

[bmxfelon420]

delete the cache on your client and let it reinstall. When i was messing with my server it seems that the class definitions have to match between the client and server. I.e. running a FML server, you cant connect to a vanilla client because of this. So i'd try to reinstall your client first.