On Linux, we do not have such a good Twitter client for so long. Most of them are just a kind of toy, not usable especially for production and professional twitter-er who need something reliable and fast. Mitter is not my project and I am not project owner. My role is actually just contributor in term of issues, bugs, patches and packaging for Debian-based distributions.
If you want pure Twitter client, Mitter is the best choice for you. Simply adding below lines to /etc/apt/sources.list and you will be able to apt-get install mitter.
deb http://ppa.launchpad.net/sugree/ubuntu hardy main deb-src http://ppa.launchpad.net/sugree/ubuntu hardy main
Note that I am not project owner :)
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