ACTOR James Farentino has been charged with stalking his ex-girlfriend, producer Tina Sinatra, daughter of Frank. After their stormy five-year romance ended in January, Sinatra obtained a restraining order against Farentino. Since then, Los Angeles prosecutors say he has sent threatening messages to her and made annoying telephone calls. He has been charged with ignoring a restraining order and violating California's stalking law. Farentino, star of half-a-dozen short-lived TV series and several TV movies, has been quiet about the charges but his lawyer vehemently denies them. Farentino is due in court on August 27.