Since you're using an ubuntu variant you could use the PPA, 3.0.5 leads me to believe you're on quantal official repos only? Or, which version of "ubuntu" are you using?
Official PPA from
https://launchpad.net/~hydr0g3n/+archive/ppa
oneiric is current to 3.0.6
precise and quantal are 3.0.8
# qBittorrent Stable (Ubuntu 11.04 "Natty" and 11.10 "Oneiric")
sudo add-apt-repository ppa:hydr0g3n/ppa
# qBittorrent Stable (Ubuntu 10.04 LTS "Lucid" and 10.10 "Maverick")
sudo apt-add-repository ppa:surfernsk/internet-software
# qBittorrent Unstable (Ubuntu 11.04 "Natty" and 11.10 "Oneiric")
sudo add-apt-repository ppa:hydr0g3n/qbittorrent-unstable
Then install qBittorrent by doing this:
sudo apt-get update && sudo apt-get install qbittorrent
Looks like this still needs to be updated for the latest versions, but the top stable one is likely the one you want to use (for oneiric, precise, and quantal). Unstable PPA doesn't seem to be updated much anymore.
Yeah it seems ubuntu repos are pretty outdated even for quantal, use of the PPA is recommended... by me at least.