Please specify option's (configurable product)

[typhoidmig]

I am using same magento cart in my theme just using custom configurable swatches and i am passing the same value as the magento is passing like for color i have 

1. form_key:
   NaM6uzfjbnmW9zcF
2. product:
   165
3. related_product:
   3
4. price:
   3
5. guarantee:
   guarantee
6. delivery:
   delivery
7. super_attribute[151]:
   6
8. super_attribute[157]:
   6
9. qty:
   1

these are my form datas but when i create product without color attribute the cart really does work but when using size it doesnt work. Any help would be heartly appreciated