Can't compile Blink

Hi there.

Just getting set up for the first time, and have hit a brick wall.

When compiling the example Blink, I get the error:

In file included from Blink.cpp:8:
C:\Documents and Settings\david.clarke\My Documents\Downloads\Arduino\arduino-1.0-windows\arduino-1.0\hardware\arduino\cores\arduino/Arduino.h:212:26: error: pins_arduino.h: No such file or directory

My environment:

Board: Arduino Ethernet
OS: Windows XP
Arduino version: 1.0

I have replaced my boards.txt with one from http://arduino.cc/en/uploads/Main/boards.txt and have selected Arduino Ethernet in the Arduino environment.

I can see various pins_arduino.h in C:\Documents and Settings\david.clarke\My Documents\Downloads\Arduino\arduino-1.0-windows\arduino-1.0\hardware\arduino\variants\standard, micro, mega, leonardo and eightanalogueinputs.

In case it's relevant, this is the Arduino Ethernet section of my boards.txt:

uno.name=Arduino Ethernet (with USB2Serial module)
uno.upload.protocol=stk500
uno.upload.maximum_size=32256
uno.upload.speed=115200
uno.bootloader.low_fuses=0xff
uno.bootloader.high_fuses=0xde
uno.bootloader.extended_fuses=0x05
uno.bootloader.path=optiboot
uno.bootloader.file=optiboot_atmega328.hex
uno.bootloader.unlock_bits=0x3F
uno.bootloader.lock_bits=0x0F
uno.build.mcu=atmega328p
uno.build.f_cpu=16000000L
uno.build.core=arduino

What am I not configuring here?

Found a solution to this, now. Replacing the boards.txt was not a good idea. The one supplied with V1.0 is correct. The one I obtained is in a different format, and importantly had this line missing:

ethernet.build.variant=standard

Thank you! I ran into the same problem when using the standalone "Atmega328 on a breadboard" setup with Arduino 1.0, and appending "atmega328bb.build.variant=standard" to its section of the boards.txt file resolved the issue.