The Online Help describes how to add a border to a text box, but doesn’t seem to indicate how one would add a non-printing border.
Edit: Re-reading your answer, it’s now unclear to me whether your issue is that you don’t want the border to print, or that you do want the border to print, but it is not being printed. Could you clarify?
If we can’t find an answer for you in the next week or so, it’s possible that the feature doesn’t exist yet.
If that’s the case, please file an enhancement bug and provide as much information about this new feature as possible. Don’t forget to mark your bug as an ‘enhancement’. The QA team will be happy to help you triage your feature request in the bugtracker.
Please post a link to any bugs you file in a comment below using the format “fdo#123456”.