you can, in some cases, get a deed (per se) done by the bank if its an issue of x-coll.
For example, nab & cba in their loan offers and small print have all monies clauses. so while you think things might not be x-secured at the end of the day they are.
With nab you can get a deed done to remove this for @$150 but with cba you cant (or thats what cba tells me...)