[Plugin: WooCommerce – excelling eCommerce] Inventroy applied to size variations – BE MY HERO!

This should be an obvious option for a cart, but, I need your help.
Here is the situation. I am designing a site for a apparel company. They have different sizes for their tops, pants, etc. They may have 10 smalls, 13 mediums, etc. Instead of creating a product for each size i.e. small brown pants, medium brown pants, etc and controlling their stock numbers as individual items, is there a way using variations to allow them to enter stock levels for each size, not just the item.

Brown Pants
Small (10)
Medium (13)
etc…

http://wordpress.org/extend/plugins/woocommerce/