1) Add 'deb http://anjuta.org/apt ./' in your /etc/apt/sources.list
2) Create a file called /etc/apt/preferences and enter the following:
Package: anjuta
Pin: version 2.*
Pin-Priority: 990
Package: anjuta-common
Pin: version 2.*
Pin-Priority: 990
Package: anjuta-dev
Pin: version 2.*
Pin-Priority: 990
3) sudo apt-get update
4) sudo apt-get install anjuta
(anjuta-dev, if you want to write anjuta plugins)
Step 2 is really necessary because ubuntu feisty repo has a weird anjuta
version that will prevent you from installing newer anjuta versions. If
you have older anjuta version (e.g 1.2.4a), remove it first. The above repo is mainly for ubuntu feisty on i386.