Canada Southern Petroleum Ltd., Calgary, (Toronto: CSW; Nasdaq: CSPLF) rejected the offer from Canadian Superior Energy Inc., Calgary, (Toronto, Amex: SNG) to acquire the company for US$14.97 per share (C$17.10) for a total of US$217 million, (C$248 million) due to a lack of credibility. Canada Southern recommends its shareholders accept the proposal from Canadian Oil Sands Ltd., a subsidiary of Canadian Oil Sands Trust, Calgary, (Toronto: COS.UN) which is offering US$13.10 per share for a deal valued at US$190 million.