Just enable them in the inspector. Easiest is to create one field, add the outline Inspector>Appearance>Graphic (in 12), then duplicate, changing the field reference.
If this is a list view layout, enter layout mode, open Layout Setup and clear the check box that starts with the word "Delineate...".
Then go to http://www.filemaker.com/company/contact/feature_request.html and let FileMaker know how this caused a problem for you. Personally, I don't see why the FileMaker programmers made this the default option for a new layout nor why it affects the appearance of a layout when in Preview/print/pdf mode.