smtp setting is fine for at home but will not work overseas. She can receive but not send. When overseas she would be better off using webmail to read and receive emails using wifi. If she does not use wifi then she could find that has high data charges. If she wants to use the email app to send then she will have to change the smtp setting to that for the wifi which can be a pain.
The other alternative is to set up a gmail account and use it to send and receive whilst overseas forwarding mail from virgin.