I have the exact same problem, yet mine hasn't been solved. Here is my error code:
10.07 06:44:13 [server] INFO at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)
10.07 06:44:13 [server] INFO at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:453)
10.07 06:44:13 [server] INFO at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:556)
10.07 06:44:13 [server] INFO at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:78)
10.07 06:44:13 [server] INFO at org.getspout.spout.SpoutNetServerHandler.a(SpoutNetServerHandler.java:169)
10.07 06:44:13 [server] INFO at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:121)
10.07 06:44:13 [server] INFO at net.minecraft.server.NetworkManager.b(NetworkManager.java:234)
10.07 06:44:13 [server] INFO at net.minecraft.server.Packet15Place.handle(SourceFile:39)
10.07 06:44:13 [server] INFO at net.minecraft.server.NetServerHandler.a(NetServerHandler.java:709)
10.07 06:44:13 [server] INFO at net.minecraft.server.ItemInWorldManager.interact(ItemInWorldManager.java:318)
10.07 06:44:13 [server] INFO at net.minecraft.server.ItemStack.placeItem(ItemStack.java:83)
10.07 06:44:13 [server] INFO at net.minecraft.server.ItemBlock.interactWith(ItemBlock.java:84)
10.07 06:44:13 [server] INFO at org.getspout.spout.block.mcblock.CustomContainer.postPlace(CustomContainer.java:435)
10.07 06:44:13 [server] INFO at ic2.common.BlockMultiID.postPlace(BlockMultiID.java:184)
10.07 06:44:13 [server] INFO java.lang.NullPointerException