How do I assing a different minimu order per user group

[aninka]

I would like to have the ability to have two different minimum order value depending on the customer group.  My site has been set up with a minimum order value of $150.00 but some customes should have the ability to place smaller orders with a % added to the price (drop shipping)  I have added the new shopper group and the additional amount and I believe this is working correctly BUT how can I set a different minimum order amount for this user group?

Using VM 1.1.4 stable