Tabber help

Why doesn't this work though?

Global window=CreateWindow("TAB TEST",0,0,640,480,Desktop(),1+2+4)
Dim tabtextareas(10)
Dim tabpanels(10)
Global tabcount=0

tabber=CreateTabber(0,0,ClientWidth(window),ClientHeight(window),window)
SetGadgetLayout tabber,1,1,1,1

tabpanels(tabcount)=CreatePanel(0,0,ClientWidth(tabber),ClientHeight(tabber),tabber)
SetGadgetLayout tabpanels(tabcount),1,1,1,1
tabtextareas(tabcount)=CreateTextArea(0,0,ClientWidth(tabpanels(tabcount)),ClientHeight(tabpanels(tabcount)),tabpanels(tabcount))
SetGadgetLayout tabtextareas(tabcount),1,1,1,1
AddGadgetItem tabber,"New Tab",True
tabcount=tabcount+1

filemenu=CreateMenu("File",0,WindowMenu(window))
	CreateMenu("New Tab",1,filemenu)
	CreateMenu("Delete Tab",2,filemenu)
	CreateMenu("",0,filemenu)
	CreateMenu("Exit",3,filemenu)

UpdateWindowMenu window

Repeat
	Select WaitEvent()
		Case $803
			Select EventSource()
				Case window
					End
			End Select
		Case $1001
			Select EventData()
				Case 1
					tabpanels(tabcount)=CreatePanel(0,0,ClientWidth(tabber),ClientHeight(tabber),tabber)
					SetGadgetLayout tabpanels(tabcount),1,1,1,1
					tabtextareas(tabcount)=CreateTextArea(0,0,ClientWidth(tabpanels(tabcount)),ClientHeight(tabpanels(tabcount)),tabpanels(tabcount))
					SetGadgetLayout tabtextareas(tabcount),1,1,1,1
					AddGadgetItem tabber,"New Tab"
					tabcount=tabcount+1
				Case 2
					If SelectedGadgetItem(tabber)>-1
						RemoveGadgetItem tabber,SelectedGadgetItem(tabber)
						FreeGadget tabpanels(SelectedGadgetItem(tabber))
						tabcount=tabcount-1
					EndIf
			End Select
		Case $401
			Select EventSource()
				Case tabber
					For i=0 To tabcount-1
						If i=EventData()
							ShowGadget tabpanels(i)
						Else
							HideGadget tabpanels(i)
						EndIf
					Next
			End Select
	End Select
Forever
End