$.keys is not a function when selecting a variant on the product show page

[mcaraway]

I am trying to integrate spree_variant_options to my new store. I am using spree 1.1.3. When I select a variant on the product show page the price is never updated.

In the console of firebug I see this error: $.keys is not a function

I noticed you tried to extend jquery with that new function. Do you have any idea why this would fail?

[rkrdo]

I'm also having this issue on a Heroku production environment, the weird thing is it works perfectly fine on my local environment