[flexcoders] Flex 3 -> 4 migration and s:States

[bu4fred]

I'm migrating a flex 3.0 application to 4.0 (or 4.5, doesn't matter much) and I 
want to use the new state features of includeIn and excludeFrom.  I have a user 
defined base class in mxml and i inherit from that for my 'working' classes.  I 
have this code in my baseclass

<mx:TitleWindow xmlns:fx="http://ns.adobe.com/mxml/2009"; 
                xmlns:s="library://ns.adobe.com/flex/spark" 
                xmlns:mx="library://ns.adobe.com/flex/mx"
                xmlns:com="components.*" 
                currentState="Oct2010">
        
        <mx:states>
                <s:State id="Oct2010" name="Oct2010"/>
                <s:State name="Oct2011"/>
                <s:State name="Apr2012"/>
        </mx:states>
. . .

------------- working class contains -----------------------------
<mx:FormItem  includeIn="Apr2012">
                        ...             
</mx:FormItem>
---- and the error is --------------------------------------------

State 'Apr2012' was referenced without being declared.  A.mxml  line 66 
/MdsClientBeta1/src/sections    Flex Problem

------------------- comments ------------------------
I tried s:states rather than mx:states but it could not resolve name
Must s:states be used only in s: components or can they be used in mx 
components?