Africa Cup of Nations debutants Madagascar produced another upset to beat DR Congo 4-2 on penalties after a 2-2 draw and seal a quarter-final spot.In a thriller, Madagascar took a surprise lead through Ibrahim Amada's superb 20-yard strike before Cedric Bakambu equalised with a header.The Indian Ocean islanders restored their lead through Faneva Andriatsima's header before Chancel Mbemba's 90th minute equaliser forced extra-time.Madagascar scored all their penalties.In contrast, DR Congo missed two, with Everton winger Yannick Bolasie's attempt going over the bar to confirm Madagascar a quarter-final against Ghana or Tunisia in Cairo on Thursday.