The EFT Module in The Raiser's Edge separates the Authorization Code and the Rejection Code into two separate fields.  
When processing credit card transactions without the EFT Module, the Authorization Code and Rejection Code appear in the same field.

If using the EFT Module, add the Rejection Code Field to the existing Batch Template:
  1. From the Batch, select Tools > Edit Batch Setup
  2. Select the Fields tab
  3. Select the Rejection Code field
  4. Click the Right Arrow Button ( > ) to bring the field into Batch
  5. Select 'Data Entry' to return to Batch