James Butler, who fights under the nickname "The Harlem Hammer" pleaded not guilty in Los Angeles on Friday to charges that he used a hammer to murder Sam Kellerman and then torched Kellerman's Hollywood apartment.  According to the Associated Press, Butler was charged with murder and arson following his Wednesday arrest and was being held on $1.25 million bail.  Kellerman, brother of well-known boxing announcer Max Kellerman, was found dead Sunday at his apartment and his hcar was missing. Authorities believe he was killed on Oct. 12, according to a district attorney's statement.