another bumper question

[bmw4life13]

i recently got into a fender bender in my e36, as some of you might have already read my other post. i've got this nasty gouge on my rear bumper.....it looks like someone took a knife and gouged it. the bumper is not cracked or anything but it does look disturbing every time i look at it. it is a linear defect ~5 inches in length x 1/2cm in depth & width on the lower rear bumper. i will try and post a picture of it as soon as i can borrow my friend's digi cam. does anyone have any ideas on what i can use to repair this area. somebody suggested melting rubber into it but i don't see that working. any suggestions would be much appreciated.