Max Horvath has released a new version of his PHPTypeSafe (a tool to give you type safety for method calls). Now it's compatible with the upcoming PHP 5.3 release too.

It is now compatible with the current version of PHP 5.3 (right now it is RC2). I think we won't see any major changes with the namespace handling in PHP 5.3 anymore, so I felt I could upgrade the library.

You can clone the source for the tool from its github page and check out the blog post for an example of it in use.