Check out the changes.txt file.  It has information on this:
* The receipts option in the admin will set the default recipts 
  check box option in the batch window.  If receipts are enabled,
  Emerald will mail out a notice to the user during the import
  phase, with either a declined or processed notice.  Three reports
  are on the ftp site (/emerald/reports) named ccreject.rpt (failed
  CC transactions), ccemail.rpt (approved CC transctions), and 
  receipt.rpt (receipt to print on the payment window).
--Dale E. Reed Jr. Emerald and RadiusNT/X__________________________________________IEA Software, Inc. www.iea-software.com
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