After installing to the newest version 4.5.6001.22159 intallation works.
For anybody else who tries to update MSI and runs into troubles here is how I solved it.
Intalling failed because I had no access to HKLM\Software\Microsoft\CurrentVersion\Unistall\KB893803v2
After reading a lot on the web the best guess (well did now work for me) would be installing subinacl.msi and create a cmd file like described here: http://social.answers.microsoft.com/Forums/en-GB/w7performance/thread/9da312d2-c99b-4283-a275-e74d93dcc366
Of course it did not work for me.
I booted into save mode. Logged in as admin and set the permissions on the registry key manually. Reboot and install worked.