Car goes back on a hill

[Copiersteve]

Hi,I hope someone can help me,I have just purchased a passat 2litre diesel 136bhp auto estate it has done 114,000 miles registered January 2006.
Everytime I am on a hill the car wants to roll back so if I let go of the brake and press the accelerator there is a slight delay so the car can roll back six feet or so,I have to hold the brake with my left foot and then press the accelerator with my right until I feel it biting.
Any help would be much appreciated.
Thank you Steve