Rabbithole excavator/quarry with refuel and continue-feature

Hey,
I wrote a rabbithole excavation/quarry program with automatic refuel, ender chest dropoff and continue feature.

http://pastebin.com/nFE04Eyh

pastebin get nFE04Eyh ex

place down turtle and a chest behind it (only if NOT using ender chest mode)

Usage:
ex length, width, depth, ignoreCount, [-e | –enderchest]

IgnoreBlocks go in slot 1 to ignoreCount.
enderchest goes in slot 15 (if needed).
fuel goes in slot 16.

The program will compare mined blocks to the fuel in slot 16 and try to always keep a full stack of fuel.

If you start the program with the continue parameter ("ex continue"), it will continue a previous excavation.
So if the program was canceled, the server crashed or the chunk was unloaded the program will continue to run correctly.
To automatically continue put the following in your "startup" file

os.run({}, "ex","continue")

A lava-bucket-refuel feature is planned.

edit: java exception bug fixed. spelling mistakes fixed :)/>

edit2: ender chest dropoff is ready

edit3: fixed some minor bugs

please tell me what you think.

any suggestions, additions or fixes ?

What do you write down for the last command, the [-e or –enderchest], im new in computercraft and dont get what i have to write down there.

also is it os.run or shell.run?

you can either use -e or –enderchest it does the same. or you could just leaf it for normal chest mode. i tried to make the command in unix style :D/>

os.run but shell.run should work too

From where it starts to dig the area? the turtle starting position.