[Alan Collett]

1. Obtain the long form birth certificate.

2. Scan and email it to the Department of Immigration at this email address:
branch1.docattach@immi.gov.au ; ensure your visa application file reference and the main applicant's full name are noted in the Subject Line of the email.

You shouldn't have to send the original (or a certified copy) to the Skilled Processing Centre, as they are happy to accept scanned documents these days.

Hope this helps.