How can I change sender of notification e-mails?

Hi folks,

I have Protected Content configured to send and automated e-mail notification on "Signup Completed for Membership". Two questions if I could:

1. The notification e-mails come from "WordPress <wordpress@positivenow.ie>" - how/where can I change this please?
2. Is there a way of including %password% in the body of the e-mail as a membership variable?

Many thanks,

Richard