Chennai, Dec 12 : Calling actor Rajinikanth his inspiration, one of Tamil cinema's fastest rising young stars, actor Sivakarthikeyan on Sunday said that every second that he interacted with Rajinikanth was special. The young actor, who commands a huge fan base across the south, on Sunday took to Twitter to greet Rajinikanth, who celebrates his 72nd birthday. Sivakarthikeyan said, "Happy birthday to my inspiration Superstar Rajinikanth sir. Always got very few seconds to interact with you but every second was special and it gave me the extra energy to work harder. Love you sir." Sivakarthikeyan was among scores of film celebrities who greeted Rajinikanth on this birthday. Birthday wishes continued to pour in from across regions and fields. Malayalam superstar Mammootty took to Twitter to greet good friend Rajinikanth. He said, "Wishing you a very happy birthday dear Rajinikanth. Stay healthy and blessed as always." Actors Vijay Sethupathi, Vishnu Vishal, Hansika Motwani, Sakshi Agarwal, Shanthanu Baghyaraj, Sibi Sathyaraj, Arjun Das, directors Karthik Subbaraj, P.S. Mithran, Venkat Prabhu, Seenu Ramasamy, music director D. Imman and producer Kalaipuli S. Thanu were among the first to greet the Tamil cinema icon. /IANS