I was running a build craft server, and had several robots going a couple of lumber jacks, a picker, a planter and a delivery bot. I had a furnace with 3 cobble stone pipes and a dock on each and an emerald and chip on each I was tinkering with the top pipes trigger. It was set as if empty, request (birch, oak, (that red type of wood)) . I was cycling through the trigger condition when the server crashed and it would not restart.

here is the inital crash report:
---- Minecraft Crash Report ----
// Don't do that.

Time: 27/11/14 10:18 PM
Description: Ticking block entity

java.lang.ClassCastException: buildcraft.api.statements.StatementParameterItemStack cannot be cast to buildcraft.transport.statements.TriggerParameterSignal
at buildcraft.transport.statements.TriggerPipeSignal.isTriggerActive(TriggerPipeSignal.java:66)
at buildcraft.transport.Gate.isTriggerActive(Gate.java:520)
at buildcraft.transport.Gate.resolveActions(Gate.java:412)
at buildcraft.transport.Pipe.updateEntity(Pipe.java:215)
at buildcraft.transport.TileGenericPipe.func_145845_h(TileGenericPipe.java:383)
at net.minecraft.world.World.func_72939_s(World.java:1939)
at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:489)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:636)
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:334)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Stacktrace:
at buildcraft.transport.statements.TriggerPipeSignal.isTriggerActive(TriggerPipeSignal.java:66)
at buildcraft.transport.Gate.isTriggerActive(Gate.java:520)
at buildcraft.transport.Gate.resolveActions(Gate.java:412)
at buildcraft.transport.Pipe.updateEntity(Pipe.java:215)
at buildcraft.transport.TileGenericPipe.func_145845_h(TileGenericPipe.java:383)

-- Block entity being ticked --
Details:
Name: net.minecraft.src.buildcraft.transport.GenericPipe // buildcraft.transport.TileGenericPipe
Block type: ID #181 (tile.pipeBlock // buildcraft.transport.BlockGenericPipe)
Block data value: 0 / 0x0 / 0b0000
Block location: World: (175,71,-1766), Chunk: (at 15,4,10 in 10,-111; contains blocks 160,0,-1776 to 175,255,-1761), Region: (0,-4; contains chunks 0,-128 to 31,-97, blocks 0,0,-2048 to 511,255,-1537)
Actual block type: ID #181 (tile.pipeBlock // buildcraft.transport.BlockGenericPipe)
Actual block data value: 0 / 0x0 / 0b0000
Stacktrace:
at net.minecraft.world.World.func_72939_s(World.java:1939)
at net.minecraft.world.WorldServer.func_72939_s(WorldServer.java:489)

-- Affected level --
Details:
Level name: world
All players: 1 total; [GCEntityPlayerMP['Soulcat1'/46188, l='world', x=177.63, y=69.00, z=-1764.42]]
Chunk stats: ServerChunkCache: 794 Drop: 0
Level seed: -6963525214504478758
Level generator: ID 00 - default, ver 1. Features enabled: true
Level generator options:
Level spawn location: World: (-184,64,256), Chunk: (at 8,4,0 in -12,16; contains blocks -192,0,256 to -177,255,271), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 21118049 game time, 21580560 day time
Level dimension: 0
Level storage version: 0x04ABD - Anvil
Level weather: Rain time: 85519 (now: false), thunder time: 145280 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:636)
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:334)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)

-- System Details --
Details:
Minecraft Version: 1.7.10
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 1791565496 bytes (1708 MB) / 2142765056 bytes (2043 MB) up to 2142765056 bytes (2043 MB)
JVM Flags: 2 total; -Xmx2G -Xms2G
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 15, tallocated: 95
FML: MCP v9.05 FML v7.10.85.1230 Minecraft Forge 10.13.2.1230 21 mods loaded, 21 mods active
mcp{9.05} Minecraft Coder Pack Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
FML{7.10.85.1230} Forge Mod Loader Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Forge{10.13.2.1230} Minecraft Forge Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
CodeChickenCore{1.0.3.23} CodeChicken Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Micdoodlecore{} Micdoodle8 Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
NotEnoughItems{1.0.3.51} Not Enough Items Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Core{6.2.0} BuildCraft Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Transport{6.2.0} BC Transport Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Silicon{6.2.0} BC Silicon Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Builders{6.2.0} BC Builders Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Energy{6.2.0} BC Energy Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Factory{6.2.0} BC Factory Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
craftguide{1.6.8.1} CraftGuide Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Dynmap{2.0.0-61} Dynmap Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
GalacticraftCore{3.0.6} Galacticraft Core Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
GalacticraftMars{3.0.6} Galacticraft Planets Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
inventorytweaks{1.59-dev-152-cf6e263} Inventory Tweaks Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
JABBA{1.1.4} JABBA Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
LunatriusCore{1.1.0.8} LunatriusCore Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
neiintegration{1.0.0} NEI Integration Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Schematica{1.7.0.80} Schematica Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Profiler Position: N/A (disabled)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Player Count: 1 / 20; [GCEntityPlayerMP['Soulcat1'/46188, l='world', x=177.63, y=69.00, z=-1764.42]]
Is Modded: Definitely; Server brand changed to 'fml,forge'
Type: Dedicated Server (map_server.txt)

Will fix in 6.2.1 which might be out today or tomorrow.