Just a quick post here to say that I have released a VirtueMart shipping module for Joomla 1.5.
Suffice to say that it provides a flexible mechanism for calculating shipping with separate scales for “Domestic” and “International” orders.
The idea for this module, plus core source code, was derived from an existing module “flex” by Micah Shawn which is contained in the current VirtueMart distribution.
You can download the module from HERE. Installation instructions are in the included README file.