Problems installing mysql

[bear]

I've read the threads here about installing mysql and also there is one under Success stories but I can't get mysql-server to work on my sheevaplug.

I've done
apt-get update; apt-get dist-upgrade; apt-get autoremove

I have apache2 and php5 installed in my system.

Then if I wan't to install mysql-server I get this:

>apt-get install mysql-server
....
(Reading database ... 15077 files and directories currently installed.)
Unpacking mysql-server-5.0 (from .../mysql-server-5.0_5.1.30really5.0.75-0ubuntu10_armel.deb) ...
Aborting downgrade from (at least) 5.1 to 5.0.
dpkg: error processing /var/cache/apt/archives/mysql-server-5.0_5.1.30really5.0.75-0ubuntu10_armel.deb (--unpack):
 subprocess pre-installation script returned error exit status 1
Errors were encountered while processing:
 /var/cache/apt/archives/mysql-server-5.0_5.1.30really5.0.75-0ubuntu10_armel.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

I also tried to install mysql-server-5.1 which at least installs but then php5 for some reason reports that mysql extension isn't installed, which it is.

Is there someone who have a clue how I could resolve my issues to get mysql server installed?