InOutContainer error

[inag29-zz]

Hello,

I am trying to create a module with InOutContainer and when I drag and drop the module it shows me this Error:

Error Layer.addContainer: WireIt unable to find klass from xtype: 'WireIt.InOutContainer'

I am using the example from here(http://dev.lshift.net/james/wireit/wireit/guide.html#InOutContainer)

{
"name": "InOut test",
"container": {
"xtype":"WireIt.InOutContainer",
"inputs": ["text1", "text2", "option1"],
"outputs": ["result", "error"]
}
}

but still I have this error.