1- get a linux-2.6.10 kernel
2- patch with acpi-ec-2.6.10.diff
     cd /source/to/linux-2.6.10
     patch -p1 -i /path/to/acpi-ec-2.6.10.diff
3- configure kernel and select ACPI and i2c support (i2c-dev is also required)
4- compile and reinstall the new kernel
5- compile i2c-acpi-smbus, for this, go to the directory smartbatt/i2c-acpi-ec/
      then issue a
      $ sh compile.sh
6- install the kernel module via:
      # modprobe i2c-dev (if compiled as module)
      # insmod ./i2c-acpi-ec.ko
7- compile smartbattery.c via something like this :
      $ gcc -W -Wall -I./include -O2 -o smartbattery smartbattery.c
8- then issue ./smartbattery <i2c bus> where <i2c bus> is the one taken from
Error: No i2c-bus specified!
Syntax: smartbatt I2CBUS
  Installed I2C busses:
      i2c-0       unknown         ACPI EC SMBus adapter at 0018           Algorithm unavailable

here it will be 0.

Good luck and happy new years!