[flexcoders] Required property not toggling off in form item.

[luvfotography]

I toggle the 'required='true' property on a text form item, and the
red asterisk disappears, yet the field is highlighted in RED and acts
as though required="true" is still applied.  Here is my code (click on
'Forget your pw?" to recreate the error.) I'm using Flex V3.

thanks,

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"; width="474"
height="483" layout="absolute">
<mx:Script>
        <![CDATA[
                import mx.events.ValidationResultEvent;
                import flash.events.MouseEvent;
        import mx.controls.Alert;      
        ]]>
</mx:Script>
        <mx:EmailValidator  id="v_email" source="{email}" property="text"/>
        <mx:StringValidator id="v_password" source="{mypassword}"
tooLongError="Password must be between 6 and 8 chars"
tooShortError="Password must be between 6 and 8 characters."
property="text" maxLength="8" minLength="6" />
        <mx:StringValidator id="v_screenname" source="{screenname}"
tooShortError="Screen name must be at least 2 characters."
property="text"  minLength="2" />
        <mx:Canvas width="100%" height="100%">
                <mx:Form x="0"   labelWidth="133"  paddingTop="0"  width="100%"
height="50%" defaultButton="{manageAccountSubmit}">
                <mx:FormHeading label="Your Account" />
                <mx:FormItem  label="Your Email Address" required="true">
            <mx:TextInput id="email"  />
        </mx:FormItem>
        <mx:FormItem   id="mypw" label="Password" required="true">
            <mx:TextInput id="mypassword" displayAsPassword="true"/>
        </mx:FormItem>
        <mx:FormItem   id="fiScreenname" label="Screen Name"
required="true">
            <mx:TextInput id="screenname" />
        </mx:FormItem>     
            <mx:FormItem>
                  <mx:CheckBox id="forgotpw" label="Forgot your Password?"
                         click="fiScreenname.required=!fiScreenname.required;
mypw.required=!mypw.required;"/>
                </mx:FormItem>
            <mx:FormItem>
                  <mx:Button id="manageAccountSubmit" label="Submit"  />
        </mx:FormItem>
        </mx:Form>
</mx:Canvas>
</mx:Application>