The ATO has recently issued two private binding rulings which broadly accepts that a SMSF can borrow from a related party at a 0% interest rate when investing in a geared fund asset – albeit a cautious approach should still be applied in my opinion.
http://ato.gov.au/rba/content/?ffi=/misc/rba/content/1012414213139.htm
http://ato.gov.au/rba/content/?ffi=/misc/rba/content/1012396819768.htm