RPG III input fields

Input fields display as a field with a single underline. Can I change the looks of the input field, either by making...

the underline thicker (a different ASCII character, through assembler, C, post-processing of display files, etc.), by drawing a box inside the input field at its outer edges, by alternating the underline so it appears as a dashed-underline, by reversing video for the field (I have to be able to display the underline as green or white, so reversing video may not work),or something similar.

I'm not allowed to have any characters blinking. I'm restricted such that I can't use different colors other than green or white for the color of the input line. Whatever I do I have to do within the confines of the input field itself: I don't have the freedom to use the spaces surrounding the input field.

Is something workable, or is this an impossibility? I'm going to be using RPG III.

You can use CHGINPDFT on your field name to replace the underline with something else ex. CHGINPDFT(CS) to use column separators, or you could do a combination such as CHGINPDFT(RI CS) to have the field be reverse image and to use column separators.