Hi 42and1, Check out the "Paypal Options" section there is a "Signup Confirmation Email (Standard)" section that you can edit the content of the confirmation email.
You can also edit the "Specific Post/Page Confirmation Email (Standard)" under Paypal Options.
Build Version: 110605 Pretty sure it was there in previous builds too
I'm having similar issues with my site as well, it doesn't seem to be affecting all users but certain ones that use CCs to pay for the subscription never get their username and password email. I am also using buddypress is this a s2 issue or a general wordpress not sending emails issue?