Skype provides Ubuntu or Debian 32bit package, but I have a small problem with it. The avatar doesn't show up, there must be a library missing. Skype didn't output any errors, therefore I have no clue to know. By installing the static, the problem is solved naturally. I installed in this way 
mkdir -p ~/{lib,bin}
cd ~/lib
wget http://skype.com/go/getskype-linux-static
tar xf skype*
cd skype*
ln -sv ~/lib/skype*/skype ~/bin
I created an application launcher in GNOME with command like 
skype --resource=/home/username/lib/skype_static-2.0.0.72
I know Ubuntu uses multilib, but not sure how to install a 32bit package via apt-get. On Fedora with Yum, you only need to append .i686 to package name, or any other arch.