The latest stable release of Konversation at the time of Kubuntu's release is available in Kubuntu's regular package archive, just sudo apt-get install konversation or use the KPackageKit package manager to install it.
For stable releases occurring after Kubuntu has been released, they are usually made available through the official Ubuntu backports. To enable this:
- Open KPackageKit from the KMenu
- Go to the Settings pane, and click "Edit Software Sources"
- In the Updates tab of the dialog that follows, check the "Unsupported updates" checkbox
- Close the dialog and KPackageKit should reload the software sources
- Upgrade as normal.
Development versions of Konversation are usually uploaded to the development version of Kubuntu during the course of the development cycle.