mixing of varchar and text functionality

Scenario: a scrolling form (timesheet) with an "activity description" field. I'd like to be able to treat the field as a varchar (direct typing into the field) if it's 65 characters or less, OR allow the user to hit "!" and fire up emacs or vi if they want to type a thesis. Is there any (inelegant is fine) way to accomplish this? This is with OnLine 5.01 on a Sparc with 4GL 4.10 --- In-Real-Life: John Bossert, Thalatta Corporation, (+1 206.455.9838) Domain: bossert@thalatta.com Path: ...!sun!sunup!thebes!bossert