[Support] Ic2 Batpack

MY MINECRAFT KEEEPS CRASING AND GIVING ME SAVING CHUNKS AND I GET THIS I THINK ITS SOMETHING TO DO WITH BATPACK COZ OF THE FIRST LINE BUT I DONT UNDERSTAND THIS SO I NEED HELP PLZ!

java.lang.AbstractMethodError: ic2.common.ItemArmorBatpack.getProperties(Lxb;Lll;Lyq;I)Lforge/ArmorProperties;
at xb.c(EntityPlayer.java:842)
at aar.a(EntityLiving.java:499)
at xb.a(EntityPlayer.java:744)
at aar.e(EntityLiving.java:717)
at xb.e(EntityPlayer.java:1413)
at ms.a(Entity.java:664)
at ms.b(Entity.java:543)
at uh.b(SourceFile:60)
at aar.a_(EntityLiving.java:811)
at xb.a_(EntityPlayer.java:1310)
at aar.d(EntityLiving.java:1003)
at xb.d(EntityPlayer.java:395)
at uh.d(SourceFile:209)
at aar.B_(EntityLiving.java:375)
at xb.B_(EntityPlayer.java:198)
at vq.a(World.java:1672)
at vq.f(World.java:1647)
at vq.m(World.java:1545)
at net.minecraft.client.Minecraft.k(SourceFile:1594)
at net.minecraft.client.Minecraft.x(SourceFile:709)
at net.minecraft.client.Minecraft.run(SourceFile:662)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT ca8c7be3 ----------

after i did that this happenes

java.lang.NoSuchMethodError: forge.ForgeHooks.onItemPickup(Lxb;Lfj;)Z
at fj.a(EntityItem.java:144)
at xb.l(EntityPlayer.java:438)
at xb.d(EntityPlayer.java:429)
at uh.d(SourceFile:209)
at aar.B_(EntityLiving.java:375)
at xb.B_(EntityPlayer.java:198)
at vq.a(World.java:1672)
at vq.f(World.java:1647)
at vq.m(World.java:1545)
at net.minecraft.client.Minecraft.k(SourceFile:1594)
at net.minecraft.client.Minecraft.x(SourceFile:709)
at net.minecraft.client.Minecraft.run(SourceFile:662)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT 17abb9e8 ----------