builder crashes server

[trhollywood]

every time i try and run a builder on my server it crashes. this is the crash report.

any one have ideas as to why?

---- Minecraft Crash Report ----
// Quite honestly, I wouldn't worry myself about that.

Time: 11/9/12 6:03 PM
Description: Exception in server tick loop

javax.management.RuntimeErrorException: NOT IMPLEMENTED
at buildcraft.core.EntityRobot.build(EntityRobot.java:219)
at buildcraft.core.EntityRobot.j_(EntityRobot.java:133)
at xe.a(World.java:2143)
at ie.a(WorldServer.java:570)
at xe.g(World.java:2106)
at xe.h(World.java:1987)
at ie.h(WorldServer.java:463)
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:649)
at hg.r(DedicatedServer.java:241)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:585)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:492)
at fp.run(SourceFile:818)

Relevant Details:
- Minecraft Version: 1.4.2
- Operating System: Linux (amd64) version 3.2.0-29-generic
- Java Version: 1.7.0_07, Oracle Corporation
- Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Oracle Corporation
- Memory: 207481880 bytes (197 MB) / 322174976 bytes (307 MB) up to 518258688 bytes (494 MB)
- JVM Flags: 4 total; -Xms278M -Xmx556M -XX:-UseGCOverheadLimit -XX:+ExplicitGCInvokesConcurrent
- AABB Pool Size: 3000 (168000 bytes; 0 MB) allocated, 2943 (164808 bytes; 0 MB) used
- FML: ~ERROR~ NullPointerException: null
- Is Modded: Definitely; 'forge,fml'
- Profiler Position: N/A (disabled)
- Vec3 Pool Size: 1004 (56224 bytes; 0 MB) allocated, 880 (49280 bytes; 0 MB) used
- Player Count: 0 / 5; []
- World world Entities: 0 total; []
- World world Players: 0 total; []
- World world Chunk Stats: ServerChunkCache: 0 Drop: 0
- Type: Dedicated Server

 

[Vauthil]

Since we're looking at robot entity spawning, I'm assuming this occurs once you've provided it with power (since robo-buddy doesn't appear until then).

A few questions:

Is the Builder supplied with materials to get started building?
Are these in the builder itself, in adjacent inventories, or both?
Is the demarcated area already clear of obstructions or is this at the part where robo-buddy is handling that?
If the area isn't cleared, are you on grass (dirt blocks with the grass texture on top) and are grass blocks part of what's supposed to be cleared out?

 

[trhollywood]

yes its looks like it happens as soon as robo buddy fires his laser but cant be sure on that. on grass that is cleared. yes most of the mats are in the builder to get it rolling. no the grass was there in the original so it should not clear it out. area is clear and free of of obstacles and is flat.
oh almost for got dont think it would matter but its powered by forestry's bio engine running bio.