Unable to work with product attributes

Hello

I am sorry if this issue has been addressed already, I have been searching for 2 days and found nothing so far. Here is my situation, I am using ubercart with uc_node_checkout to sell services (not goods) on my website. Each of the services has additional attributes that users can choose to add like a pickup of documents at doorstep which will add to the cost of the service. Here are the steps I followed:

1. Created product class
2. Added attributes - PickupService
3. Added the above attributes to the product class
4. Link this product to a node to collect details from user to deliver the service
4. Edit the content type associated with the product and added attribute here too

Now, when I go to purchase the product, I get the following:
"Fatal error: Call to a member function fetch() on a non-object in ../../sites/all/modules/uc_node_checkout/uc_node_checkout.module on line 1143"

If I don't add the attributes on the content type edit form, then I don't get the above error but the attributes don't show up anywhere in the checkout flow.

Please help me.. what am I doing wrong here.
Thanks in advance
-vasantha