Update 2011-06-25: As suggested in the comments just clicking back button and then next again in the installer could bypass the problem. Thanks to Hatem and tikno07.
I was trying to install the Android SDK tools using the Windows installer package recently. Since I had the Java JDK SE 6 Update 23 installed on my system I was confused about the installer aborting the installation process with the message:
Java SE Development Kit (JDK) not found
After some research I found out, that the installer does not detect 64-bit JDK versions. After removing the 64-bit version of the JDK and (re)installed the 32-bit version the installer worked as expected.
I also found this post and that one which show workarounds to get the Android SDK tools working with a 64-bit JDK. Due to the fact that I do not know if using a 64-bit JDK has any side effects on the Android tools, I decided to use 32-bit one to be on the save side.