Minecraft 1.6.4. getTexture() may be returning null. May be irrelevant now, but will safeguard against this.

java.lang.NullPointerException
at mca.client.gui.GuiVillagerEditor.drawEditorGui(GuiVillagerEditor.java:502)
at mca.client.gui.GuiVillagerEditor.func_73875_a(GuiVillagerEditor.java:170)
at net.minecraft.client.gui.GuiScreen.func_73864_a(SourceFile:69)
at mca.client.gui.GuiVillagerEditor.func_73864_a(GuiVillagerEditor.java:415)
at net.minecraft.client.gui.GuiScreen.func_73867_d(SourceFile:128)
at net.minecraft.client.gui.GuiScreen.func_73862_m(SourceFile:107)
at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1566)
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:910)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:838)
at net.minecraft.client.main.Main.main(SourceFile:101)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:131)
at net.minecraft.launchwrapper.Launch.main(Launch.java:27)