just installed v8.0.6312(beta-3)
Tried to create a 1024GB thin LUN, but failed with error message, see pic below.
http://i44.tinypic.com/t69w93.png (full image)

http://oi44.tinypic.com/t69w93.jpg (RAW image)
I have 12GB RAM, about 2G is been used.
I have 4TB SAS, about 2TB free.
I tried creating a 10GB LUN, I did not get that error.
I tried 100GB LUN, did not get that error.
tried 500GB LUN, no error
tried 900GB LUN, no error
Tried 1024GB LUN, error
Tried 1TB LUN, error.