By United Press InternationalTHURSDAYCBS Thursday Movie. “Guess Who’s Coming to Dinner.” Rerun aibout a white liberal couple (Spencer Tracy, Katherine Hepburn) whose beliefs are tested when their daughter returns from a holiday with a prospective husband who is black (Sid ney Poitier). Katharine Houghton, Miss Hepburn’s niece, plays the daughter. With Cecil Kellaway, Beah Richards. 8o.m. CDT.Dinah’s Place, NBC. Ex-profootball player Fred Williamson, star of the movie “The Legend of Nigger Charley,” visits. 9 a.m. CDT.The Waltons. CBS. John, who practices his religion with leeway, and Olivia, more strict about it, have the first serious quarrel of their 18 year - old marraige when she agrees with a zealous young minister who exhorts the children to give up their “evil ways” or suffer eternal damnation. The ministeris played by John Ritter, son od western actor - singer Tex llitter. 7 p.m. CDT.Flip Wilson, NBC. With Diana Sands, David Steinberg. The Jackson 5. 7 p.m. CDT.InternationalPBS. “Phcdre,”Performance, a ballet basedon Greek mythology’ with text by Jean Cocteau, and produced for French television, is featured. 8 p.m. CDT.Dean Martin. NBC With William Conrad. 9 p.m. CDT.