Sky+ and Philips DVDR3300H

Hi,
I have some programmes recorded on my Sky+ box and want to put them on to my Philips DVDR3300H in order to be able to burn them to dvd, these are not recorded from Box office, the method I use is to play on the Sky+ and record on Philips DVDR3300H , but once the programme is on the hard disc, the option to copy to dvd is greyed out, does anyone know how to get around this problem?
thanks,
Noel