To my utter surprise the GyachI version 1.1.0-1 debian (.deb) package for Ubuntu Dapper installed right away and is working fine.
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This Yahoo! client for Linux operating system supports almost all of the features you would expect to find on the official Windows Yahoo! client: Voice chat, webcams, faders, 'nicknames', audibles, avatars, display images, and more. Yet, it remains very light-weight and memory-friendly. GyachE Improved uses Gtk-2 for its user interfaces (Gtk-2 2.0.6 or better required).