dynamically update webform submitted fields using rules
===

I am newbie to drupal and seeking help in creating rules for dynamically updating webform fields affter submission. I created a form using webform for sponsors and redirected after save to ubercart product for payment. Now I have to create a rule according to the product(Platinum Sponsorship/Gold Sponsorship) and update the sponsorship field on order completion. I created the rule but stucked while setting value of the field (rule action) sponsor to (platinum/gold) as webform fields are not appearing in data selector.