BERLIN (Reuters) - German Chancellor Angela Merkel on Friday forcefully rejected a letter from Iranian President Mahmoud Ahmadinejad seeking cooperation with Germany, saying it did not even deserve an answer. Iranian Foreign Minister Manouchehr Mottaki delivered the letter to the German embassy in Tehran earlier this week. A German government official who saw the letter told Reuters it criticised Israel and said Germany and Iran should cooperate in dealing with Zionism and solving the Palestinian problem. "He's repeating the old thinking, which is totally unacceptable to us," Merkel told ZDF state television. "Israel's right to exist is a key part...