AusPostPAC1
Employs the AusPost Postage Assessment Calculation API - Tested in PAC 1.3 and PAC 1.4 (latest at 21/04/2013).
Supports: Domestic|International, Parcel|Letter, Regular|Express, Registered, Confirmed, and Insured Post.
For multiple cart products: Calculates parcel sizes and splits into multiple parcels where required as per AuPost parcel limits.
Tested in Joomla 2.5 with VirtueMart 2.0 so far, if you get her running in J3 please let me know :)
The AusPost PAC spec was impressive also and is available via the AusPost Developer Center.
To configure: First enable the plugin in "Administrator -> Extensions -> Plugin Manager", then add a new shipment method in "Administrator -> Components -> Virtuemart -> Shop -> Shipment Methods".
Further instructions at: http://shop.ekerner.com//plugins/vmshipment/auspostpac1/auspostpac1_manual.php (AusPostPAC1 Manual).
Developed by eKerner.com.au - Technical Solutions