New Delhi, Nov 16 (ANI): Bollywood actress, Katrina Kaif says she gets nervous in front of superstar of tinsel villa, Shah Rukh Khan while her ex-beau Salman Khan makes her feel comfortable. "I was nervous while working with Shah Rukh... I don't know why. There was something about him that made me nervous.. While Salman makes me feel comfortable... He has known me since beginning. Personality wise, I give Salman ten on ten," she said at the Dhoom 3 title song launch.