Is there a way to package a jar file (for example, a .deb) and install it on Ubuntu 11.10. Basically I want to automate the installation of Jar file when I create a Ubuntu VM (using KVM).
No, you cannot package/install a .jar file.
Java requires the Java Runtime Environment to run programs. You must have that installed on the client in order to run a .jar (Java executable) file.
Install the Java Runtime Environment on your client, copy the .jar, and run