Broken packages trying to get Amarok 2.1 to work on Jaunty

This is not a nice post with solutions to anyone else... only the partially successful attempts to fix my somewhat broken system.

I recently upgraded from Kubuntu 8.10/Intrepid to 9.04/Jaunty. Shortly after I installed Amarok 2.1, which was one of the few things I really wanted from Jaunty. Sadly, amarok did not play any local mp3 file. Googling around, I found that I could be missing libxine1-ffmpeg (or libxine1-allcodecs or libxine1-plugins, which depend on libxine1-ffmpeg). But I was unable to install it:

$ sudo apt-get install libxine1-ffmpeg
(...)
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
libxine1-ffmpeg: Depends: libavcodec52 (>= 3:0.svn20090303-1)
but it is not going to be installed or
libavcodec-unstripped-52 (>= 3:0.svn20090303-1) but it is not
going to be installed
E: Broken packages

This is where I got swamped in package versions. Trying to get libavcodec52 to work:

$ sudo apt-get install libavcodec52
(...)
The following packages have unmet dependencies:
 libavcodec52: Depends: libavutil49 (> 3:0.svn20090303-99) but 3:20080706-0.3lenny1 is to be installed or
                        libavutil-unstripped-49 (> 3:0.svn20090303-99) but it is not going to be installed

Let's try with libavutil49:

$ sudo apt-get install libavutil49
(...)
libavutil49 is already the newest version.
libavutil49 set to manually installed.

So libavutil is already installed... but libavcodec52 does not install! Let's try with the other dependency: install libavutil-unstripped-49:

$ sudo apt-get install libavutil-unstripped-49
(...)
The following packages will be REMOVED:
dvdrip ffmpeg k9copy ksubtitleripper libavcodec51 libavdevice52
libavformat52 libavutil49 libmjpegtools-1.9 libmjpegtools0
libpostproc51 libquicktime1 libswscale0 mjpegtools qdvdauthor
subtitleripper transcode videotrans
The following NEW packages will be installed:
libavutil-unstripped-49
(...)
Setting up libavutil-unstripped-49 (3:0.svn20090303-1ubuntu2+unstripped1) ...

At last, some package was installed. But I removed many packages on the way!! I hope I don't find I needed them...

Going backwards, I was able to install now libavcodec52, but this still does not help for libxine1-ffmpeg:

$ sudo apt-get install libavcodec52
...
Setting up libavcodec52 (3:0.svn20090303-1ubuntu6)

$ sudo apt-get install libxine1-ffmpeg
(...)
The following packages have unmet dependencies:
libxine1-ffmpeg: Depends: libavcodec52 (>= 3:0.svn20090303-1) but it is not going to be installed or
libavcodec-unstripped-52 (>= 3:0.svn20090303-1) but it is not going to be installed
E: Broken packages

So I replaced libavcodec52 by libavcodec-unstripped-52:

$ sudo apt-get install libavcodec-unstripped-52
...
The following packages will be REMOVED:
libavcodec52
The following NEW packages will be installed:
libavcodec-unstripped-52
...
Setting up libavcodec-unstripped-52 (3:0.svn20090303-1ubuntu2+unstripped1) ...

Now I can finally install libxine1-ffmpeg:

$ sudo apt-get install libxine1-ffmpeg
...
Setting up libxine1-ffmpeg (1.1.16.3-0ubuntu1) ...

(And I also installed libxine1-plugins just in case).

Now Amarok 2.1.1 can play my mp3's. But it was a painful way and I am pretty sure I have broken other things. So I wonder, if any reader got so far:

• why libavcodec52 on my Jaunty wanted to install libavutil49 versin 3:20080706-0.3lenny1 ?
  
• what's the difference between libavcodec52 and libavcodec-unstripped-52?
• how did I get to the 'broken packages' state? did I do something wrong, or are there still some packages in Jaunty with broken dependencies?