Adding a property page to project properties without implementing a project subtype

I'm developing a Visual Studio 2010 package. My package needs to add a new tab to the project properties.

All the examples that I could find on adding new tabs add the tabs by implementing project flavors or subtypes. However, I need to add the tab without creating a new project flavor. I know that this must somehow be possible, as other packages are doing it as well (for example, when you install Code Contracts, you get a new Code Contracts tab, and the Code Contracts package does not modify the project type / add a new subtype as far as I can see).

How can I add a tab to the properties of a project from a Visua开发者_运维知识库l Studio 2010 package without implementing a new project flavor?

Thanks, Mathias