CREATE TABLE table_13079788_3 (date VARCHAR(255), gtc_winner VARCHAR(255), gt3_winner VARCHAR(255))
what are all the date for gtc winners graeme mundy jamie smyth and gt3 winners hector lester tim mullen
    
SQL: SELECT date FROM table_13079788_3 WHERE gtc_winner = "Graeme Mundy Jamie Smyth" AND gt3_winner = "Hector Lester Tim Mullen"