[X4U] adding Mail to Mail.app

[nk]

I have made a powerbook serve as my Internet machine for about 4 months 
now...a G4 Mini had been doing internet, and e-mail using Mail.app.

what's the best way to get all that 4 months' worth of mail onto the G4 
Mini?  I might be able to connect the mini to the 'net, and let 
mail.app download all that mail which is "new" to it, since I turned 
off "delete mail from server" in Mail.app on the powerbook; it all 
ought to be there.

Any thoughts?

thank you!

nk