Yeah, this is something i hadn't seen before, which due to a...

Yeah, this is something i hadn't seen before, which due to a legal quirk they are allowed to do with Interim dividends, as opposed to final divs which they cannot do.

For anyone who is interested:
"Once a final dividend is declared it becomes a debt owed by the company to shareholders, and shareholders may enforce this just like any other contractual debt. [5] The directors may also declare an interim dividend when they believe the company’s profits justify such a payment. Unlike a final dividend, an interim dividend can be rescinded after it is declared but before it is actually paid. [6] Therefore, shareholders cannot enforce payment of an interim dividend, even if it has been declared."

from: section 2, pg2 http://classic.austlii.edu.au/au/journals/SydLawRw/1998/2.html