it's completely unnecessary to run a virtual machine or a chroot just for skype.
if you download the statically linked (not requiring system dependancies) skype distributable, you can run both Skype 4.0 and Skype 2.2 on the same system.
install skype 4.0 using the deb, and download the statically linked version of skype 2.2 and extract it to /opt
and then add /opt/skype-VERSION
to your $PATH
in ~/.bashrc
rename the skype
executable in /opt/skype-VERSION
to something like skype-2.2
and once you've done all of that, you should be able to run skype-2.2
and skype
for either version.
here's Skype 2.2 static: http://download.skype.com/linux/skype_static-2.2.0.35.tar.bz2
171e50e1e25cf844ff5cdf9ee66da91b0b440634 skype-ubuntu_2.2.0.35-1_amd64.deb