Nested Master Page Events not being called

This is the second time I've been caught out by this little feature, so I thought I'd geekzilla it for both reference and to help others.

Scenario

I'm a big fan of MasterPages and Themes as a design principle for web development, and often you need to nest master pages to create complex repeatable layouts.

The Feature

In my child MasterPage I decided to put some code in the Page_Load to populate a related menu, and it wasn't being called....... very strange.. The Top level MasterPages' events were being called, but the child's weren't!

Solution

I'm not sure why it defaults to false but.. you need to change the AutoEventWireup property to true in the Master Directive in the MasterPage.

If this has caught you out, here's the solution.