> * Why in your repoisitories for Jaunty there are no kubuntu-desktop-kde3 and kde-kde3? How to install it without enabling repos for other distros?

Obviously I'm just guessing here, but perhaps it has to do with the
size restrictions on PPAs. Plus, it's not enabling repos for other
distros...it's just enabling the repo originally set up for intrepid
(a different release, not a different distro)...makes sense,
considering how many things haven't changed, to have the jaunty repo
just be the updates and changes from the KDE3 release for Intrepid.
The modular and hierarchical nature of the Debian .deb/apt packaging
system makes this both the easiest and arguably the best way to
accomplish setting up the repos for Ubuntu+KDE3.