cmaglie:
may you update your repository and retry?
I did a 'git pull' and retried, but still got an error.
Tried it a second time (that's why the local repo was up-to-date) and put the log here:
http://paste.debian.net/247200
edit: 'gitb' in the paste is a local alias for 'git branch'.
so I'm on branch ide-1.5.x
dada@i5:~/Arduino$ gitb
* ide-1.5.x
edit2: as the above link was about to expire I replaced it by a new one,
expires 90d