I've been itching to try KDE3 on my laptop, but upgrading to the new KDE3 RPMS (I run RH 7.2) was proving very difficult indeed. So I took a kind of radical approach...
I first downloaded and installed apt, from Conectiva - they basically ported apt to work with RPMs.
Then I set my source.lst file to point to Conectiva's snapshot directories (kind of like a moving beta).
Then I said:
This got me some of the way, but a lot of modules failed to update (causing the whole thing to fail) due to dependencies. I removed quite a few things, then force-installed a few things, and kept trying, and eventually it all went in.
Then I removed KDE2:
rpm -e `rpm -qa | egrep ^kde`
(and also had to remove 3 modules that the above missed, that depended on KDE)
Then I installed KDE3:
apt-get install task-kde
And now I have a wonderful new working Conectiva Linux box, running KDE3.
Now a LOT of this failed along the way, and so I'm glossing over the details - remember that Red Hat and Conectiva have some very different config files, so I had to fix quite a few things, reconfigure X, and all sorts of funny bits and pieces. But yeah, now I'm running kernel 2.4.18 on my laptop with KDE3...
Now KDE3 is nice. Really nice. In fact it's absolutely gorgeous. Kmail now does IMAP just right (check mail in *all* folders for example), Kate makes for a really sweet editor, konqueror has seen some nice improvements, and generally I'm very happy with it. I think it's even a tiny wee bit faster, though I won't stake my life on it
Anyway, it was kinda fun seeing how I could cross-upgrade a machine to a completely different OS. I wouldn't say it went smoothly, but it was smoother than I honestly expected it to be. I am a happy bunny.