Water Line Connection to Dishwasher Help Needed

Hello, I am trying to install a Whirlpool dishwasher and have encountered a problem that I can't find the solution for online. The water line is plastic tubing that extends from under the cabinet's wall. I can't access the point of contact with the main water line. The previous dishwasher was connected to this plastic water line. However, I cannot get the plastic line to adequately attach to the new dishwasher. I put on a compression fitting (3/8in) and attached it, but water shoots out of the back of the fitting. The 3/8 inch sleeve does not fit the plastic piping so I tried using the brass ferrinule. No success. Can anyone recommend a good fitting? Or a trick that I'm not thinking of? Attached is a pic of the red water line connected to my house and the other is a braided line connected to the dishwasher.Attachment 42498 (http://www.doityourself.com/forum/attachments/toilets-sinks-showers-dishwashers-tubs-garbage-disposals/42498-water-line-connection-dishwasher-help-needed-imag0107.jpg)Attachment 42499 (http://www.doityourself.com/forum/attachments/toilets-sinks-showers-dishwashers-tubs-garbage-disposals/42499-water-line-connection-dishwasher-help-needed-imag0108.jpg)