You can import the mail messages under her profile when setting up OE6. If I recall there is an import wizard of some sort I think under FILE>IMPORT possibly then you pick the source identy you want to share (the one setup under your account).
Something along those lines is what you would need to do. As if I recall OE stores the mail locally as opposed to on the mail server. Just tell her to get her own account damnit..lol. j/k. Women own us I know
damn there hippnotic breasts and lucious booties.