DILLIGAF, it seems to be a problem with git:
fatal: Not a git repository (or any of the parent directories): .git
I built it successfully on 64-bit Linux Mint 13 (which is based on Ubuntu) from this package:
http://i0coin.bitparking.com/i0coin-v32509.tar.gzEDIT: Sorry, I just noticed that v32509 is ANCIENT (2011-12-22). I thought it was the latest version.