Problem User crashed server - Get error when I reboot server

[NizeGuy]

Hi there.

Someone on the server somehow managed to crash the server. It was not intended, mind you.

Whenever I try restarting the server I get this error message: (the same error message from the first crash)

---- Minecraft Crash Report ----
// Everything's going to plan. No, really, that was supposed to happen.
 
Time: 3/18/13 10:22 PM
Description: Ticking tile entity
 
java.lang.NullPointerException
    at com.eloraam.redpower.core.PipeLib.movePipeLiquid(PipeLib.java:237)
    at com.eloraam.redpower.machine.TilePipe.g(TilePipe.java:122)
    at yc.h(World.java:2153)
    at in.h(WorldServer.java:516)
    at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:680)
    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)
 
 
A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------
 
-- Head --
Stacktrace:
    at com.eloraam.redpower.core.PipeLib.movePipeLiquid(PipeLib.java:237)
    at com.eloraam.redpower.machine.TilePipe.g(TilePipe.java:122)
 
-- Tile entity being ticked --
Details:
    Name: RPPipe // com.eloraam.redpower.machine.TilePipe
    Block type: ID #0
    Block data value: Unknown? (Got -1)
    Block location: World: (-2084,48,309), Chunk: (at 12,3,5 in -131,19; contains blocks -2096,0,304 to -2081,255,319), Region: (-5,0; contains chunks -160,0 to -129,31, blocks -2560,0,0 to -2049,255,511)
Stacktrace:
    at yc.h(World.java:2153)
    at in.h(WorldServer.java:516)
 
-- Affected level --
Details:
    Level name: world
    All players: 0 total; []
    Chunk stats: ServerChunkCache: 1052 Drop: 0
    Level seed: -7155086423967967021
    Level generator: ID 00 - default, ver 1. Features enabled: true
    Level generator options:
    Level spawn location: World: (164,64,256), Chunk: (at 4,4,0 in 10,16; contains blocks 160,0,256 to 175,255,271), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
    Level time: 97694095 game time, 17660786 day time
    Level dimension: 0
    Level storage version: 0x04ABD - Anvil
    Level weather: Rain time: 141549 (now: false), thunder time: 38703 (now: false)
    Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
    at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:680)
    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)