Just now I bring Celeste, the Squeak email reader to new life in Squeak 4.3
You could test with
MCHttpRepository
    location: 'http://www.squeaksource.com/Ladrillos'
    user: ''
    password: ''
And load Network-Mail Reader-edc.26

Just test and works with yahoo, still do not with gmail, so I all ears.
Enjoy and thanks all.

Picture in http://img14.imageshack.us/img14/1446/celested.jpg

Edgar