As you might know Microsoft distributes updates and hotfixes with in installer, update.exe. When you run update.exe it looks into the supplied .inf files to see what it has to install. It’s not possible to make changes to the inf files however because that will invalidate it’s signature (and update.exe checks the signature that is stored in an accompanying .cat file).

In my case I wanted to deploy the MUI pack for Internet Explorer 7 to be able to support multiple languages. By default this pack installs 35 (!) languages and I wanted to install only Dutch language on top of existing English.