[flexcoders] Using subclassed flex controls in mxml

[whatabrain]

Let's say I subclass a control, like DataGrid:
package myStuff {
     public class CustomGrid extends CDataGrid {}
}

How do I instantiate it in an mxml file? I tried these but they didn't
work:
    <mx:CustomGrid/>
    <myStuff:CustomGrid/>

Thanks for all your help! This group is making my transition from DHTML
to Flex so much easier.