$ sudo apt-get update
$ sudo apt-get install libkopete4 

libkopete4 is installed in your system.

Make ensure the libkopete4 package were installed using the commands given below,

$ sudo dpkg-query -l | grep libkopete4 *

You will get with libkopete4 package name, version, architecture and description in a table

libkopete4 package basic information: