AAAHHHHH! Nedd help with film name please

[Dundderheed]

I saw this film in the mid ninties. A group of young people hicking/camping in the woods and they start to be picked off by physco twins wearing yellow rain coats. The twins, if i remember correctly are large and they signal to each other by whistling a tune. I think it had 'sun' in the title.

Please help it has been driving me nuts for ages:rant:.

Cheers folks

[BlackWidow]

Must be the same movie I was looking a couple of years ago... "Just before dawn" must be it.

"edit"
found a trailer and you can hear them whistling

http://www.terrortrap.com/vimedia/trlr/0022.php

watch it let me know if it is the movie

[Dundderheed]

Thats the very one, Cheers for that Blackwidow.

[Dundderheed]

I checked out the trailer and a soon as I heard the whistle I knew that was it. awesome. Thanks again.