Well the problem is it is an all or nothing thing to change it and I don't think we should have that for every page in the menu.
If it were possible to set that from code then I would add a web.config setting and code it up to accommodate you but it is not possible to do that it can only be set in the page directive.
So if you need that you'll have to edit the Default.aspx file in your copy and add that, and you will have to maintain that modification whenever you upgrade.
For supporting pages in custom features you have control over that, but in the main cms page which all are served from Default.aspx you would have to edit the file as mentioned above. And I have no idea what if any side effects that will create in mojoPortal existing features if you do that.
Best,
Joe