WP e-commerce product variations

Hi Everyone
I am building an e-commerce for a client and he sells perfume.

I need to set up for each product 3 variations:

ex. Chanel no. 5

50 ml
100 ml
5 ml

and attribute 3 different prices to each variation. I saet them up in the variations page but once i am in the product pages i can see the variation collapse menu but it won’t add any as if there we’re some sort of bug.
And i am preyy much stuck at this point.
Using WP 3.2 and wp ecommerce 3.8.6 and I have gold edition.
thanks for any help
Pier