Hi,

In need of this myself, along with recurring payments, I created this module:

http://www.ubercart.org/contrib/14613

It turns out eProcessingNetwork does not support the Authorize.net API for recurring payments, or storing customer info, so I used their "Transparent Database Engine" (TDBE) API and implemented it natively.

This is only tested on current Ubercart 2.0 releases. Recurring functionality is written for the development version of uc_recurring, and will probably not show up if you have earlier versions installed--and I was unable to properly test recurring payments in a test account...

Let me know if it works for you!

Cheers,
John