Hi,
I have the same need.
Credit card frauds on online purchases are becoming more and more frequent: people buy stuff and, as soon as it is being shipped to them, they contact the credit card issuer, in order to challenge the purchase, and get a refund.
So the seller remains without the item and the money. At present all the burden is shifted to the seller and insurance companies, but it is no fair.
I found a company named UTrust, which could help in that matter, and they have plugins for Magento and other e-commerce solutions.
They haven't made a Joomla plugin yet.
I contacted them in order to inform them about VirtueMart, they replied that they are interested, but they won't do it unless they get someone from VirtueMart to contact them.
They told me to contact VirtuMart support myself, but I don't see a quick way of doing this, and I am not even sure VirtuMart is interested in such a feature.
Which, in my opinion, should slowly become a must...