The latest version of xVideoServiceThief (2.5) switched to using the QT5 library.
To get it to work, I needed to setup QT5 on a xUbuntu 12.04.2 LTS which I did by running the following commands:
sudo apt-get install python-software-properties && \
sudo apt-add-repository ppa:canonical-qt5-edgers/qt5-proper && \
sudo apt-get update && \
sudo apt-get install libqt5gui5 libqt5webkit5 libqt5script5
Let me know in the comments if this helped you or if there were any issues.