[plt-scheme] Expanding into top-level

I have a syntax-rules macro that expands into a top-level 
definition, something like

  (define-syntax foo
    (syntax-rules ()
      [(_ name e1 e2)
       (define name (bar e1 e2))]))

Except I don't really want to define `name', I want 
to define `name-prime'.  How can I build an identifier 
and still have a top-level definition?

-- Paul (who doesn't know the macro system as well as he should)