After a long period, I just built packages of microblog-purple and Mitter for Ubuntu in Personal Package Archive. PPA is a kind of personal repository for apt-get hosted at launchpad.net. As a result, you just need to add below lines to /etc/apt/sources.list.

deb http://ppa.launchpad.net/sugree/ubuntu hardy main
deb-src http://ppa.launchpad.net/sugree/ubuntu hardy main

And simply run apt-get to install.

sudo apt-get install mitter

or

sudo apt-get install pidgin-microblog

I have just involved in new project called microblog-purple hosted at Google Code. It has such a bad name but its capability is promising. If you are using Twitter for a whlie, I guess you are waiting Twitter IM to come back. Without Twitter IM via Google Talk, there is no comparable and really usable Twitter client for any OS. The greatest feature of Twitter IM is responsiveness. I mean bi-directional highly responsible. Personally, I would love to type one tweet, press Enter, type another tweet, press Enter and so on without waiting or blocking even a second. microblog-purple now provides Twitter plugin that lets you tweet as fast as Twitter IM and configurable refresh rate.