You can install the C++ library using your package manager. As for the Java library, you can use instructions inside the source package, it's very easy to build.
After having installed that, you can create the symlink:
[based in tigase-kontalk directory]
$ cd jars
$ ln -s [location of jkyotocabinet.so in your system] .
It should be as simple as that. Be careful of your CPU and Java architecture. If you have a 64-bit system, you should use 64-bit Java.