London, Aug 9 - Drew Barrymore and boyfriend Justin Long are very passionate lovers off screen but they apparently didn't looking convincing as a couple while shooting an intimate scene for their new film.

The two have been dating on and off since 2007, but weren't passionate enough while filming scenes for 'Going The Distance' on a boat in New York this week, thesun.co.uk. quoted a source as saying.

But it was a different story on the sets. According to another source, the couple 'very passionate' and 'continued kissing even when the cameras stopped running'.