borderlayout problem

[Dextro]

I try to make a borderlayout. I have a working example. But in another place I get the following error and I really don't know the answer.

Layout = function(){
        return {
            init: function(){
               var layout = new YAHOO.ext.BorderLayout(document.body, {
               		hideOnLayout: true,
                    layoutheader: {
                        split:false,
                        initialSize: 80
                    }
                });
                layout.add('header', new YAHOO.ext.ContentPanel('layoutheader', {fitToFrame:true}));

           }
     }

}();
YAHOO.ext.EventManager.onDocumentReady(Layout.init, Layout, true);

this.regions[target] has no properties
add("header", Object closable=false loaded=false active=false)yui-ext-debug.js (line 12343)
init()layout.js (line 11)
namespace()utilities.js (line 2)
fireDocReady()yui-ext-debug.js (line 3386)
CustomEvent(DOMContentLoaded )event-min.js (line 1)
[Break on this error] return this.regions[target].add(panel);

Does someone know what goes wrong here?

[Animal]

Where in the documentation and examples do you see "header" as the name of a Region?

[Dextro]

Damn, I thought I could give it any name I want. Not very smart.

Can you give me a hint where I can find that in the documentation? Just to solve such stupid mistakes by my self the next time.

[Animal]

Go to the main page. Jack's blog has a lot of worked examples. And the "DOCUMENTATION" link works, and has examples.