How to check if some specified patch&packages installed on running

[mrly]

I used the "Search" function of forum however could not get my answer. Most topic is about how to build unattended vista on one offline image. So I open this topic and wish someone could give me some suggestion.

I want to prepare one package, it will check if some specified patch was installed on running Vista, then decide to install or not. On Window XP, I could check below registry to get the infomation HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\Windows XP\SP4\KB936059, but I found no way to check in Vista. This package will include all security patch I need target computer to be installed.