I am using Drupal 5 and Ubercart 1 and was able to get past this "Array missing" thing by the above changes, except you also need to get rid of the square brackets by dependencies, i.e.,

change this
dependencies[] = uc_product

to this:
dependencies = uc_product

I do not see any menu items in the Store Administratoin > Shop Configuration after successfully activating the module. By looking at the code, I figured to navigate to this url:
https://myubercartstore.com/admin/store/settings/uc_rss_feed
There, all I see is the message below, which looks like help info. No links or settings to configure.

- The XML Store RSS Feed, Provides Information And Links To All Your Products, For Use By Search Engines, Advertising, Price Comparison Or Web Indexing And News Services
- Here You Are Given The Flexibility To Choose Exactly Which Product Information You Want To include In Your RSS Feed.

Any ideas how to get this working with an older install?
- Ubercart Does Not Cater For Used Or Graded Products, You Are Given The Option To Specify Your Items Condition