I tried to install the mod but i would not work.
Error report:
BEGIN ERROR REPORT ab108a0 ——–
Generated 3/24/12 9:45 PM

Minecraft: Minecraft 1.2.3
OS: Windows XP (x86) version 5.1
Java: 1.6.0_31, Sun Microsystems Inc.
VM: Java HotSpot(TM) Client VM (mixed mode), Sun Microsystems Inc.
LWJGL: 2.4.2
OpenGL: Intel 865G version 1.3.0 – Build 4.14.10.4396, Intel

java.lang.NoClassDefFoundError: net/minecraft/src/buildcraft/core/CoreProxy
at AdditionalBuildcraftObjects.ABO.createPipe(ABO.java:207)
at AdditionalBuildcraftObjects.ABO.initialize(ABO.java:140)
at mod_AdditionalBuildcraftObjects.load(mod_AdditionalBuildcraftObjects.java:30)
at ModLoader.init(ModLoader.java:890)
at ModLoader.addAllRenderers(ModLoader.java:186)
at aho.(aho.java:79)
at aho.(aho.java:9)
at net.minecraft.client.Minecraft.a(Minecraft.java:395)
at net.minecraft.client.Minecraft.run(Minecraft.java:732)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: net.minecraft.src.buildcraft.core.CoreProxy
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
… 10 more
— END ERROR REPORT c3dee19e ———-