Director Prabhudheva's next directorial venture 'Rambo Rajkumar' featuring Shahid Kapoor and Sonakshi Sinha seems to have run into a bit of trouble with the title. According to reports,the makers of the original Rambo series have copyrighted the word Rambo making it unavailable for usage by other filmmakers. As a result the makers have now decided on a title change for the film. However,since the film's title is already known among the audience the makers have decided on dropping a few alphabets from the title rechristening it to R.o Rajkumar. R.o Rajkumar directed by Prabhu Dheva,produced by Eros is slated for release this December.