function hex2dec(hex){
  HexStr = '0123456789abcdef';
  hex = hex.toLowerCase();
  a = hex.substring(0,1);
  b = hex.substring(1);
  dec = 0 + HexStr.indexOf(a)*16 + HexStr.indexOf(b);
  return dec;
}

function Decode(str){
  // var str = new String(str);
  var n;
  var StrDecoded = '';
  StrLength = str.length/2;
  for (i=0; i<StrLength; i++){
    n = hex2dec(str.substring(2*i,2*i+2));
    // StrDecoded += String.fromCharCode(n - StrLength);
    StrDecoded += String.fromCharCode(n);
  }
  return StrDecoded;
}

function SendeImehl(Adressat, Text, Betreff){
  I_mehl = '';
  if (Adressat === 'Bernd_Gondro')             { I_mehl = Decode('4265726e6440476f6e64726f2e6e6574'); }
  if (Adressat === 'MKV-X')                    { I_mehl = Decode('4d4b562d58404d4b562d4d75656e6368656e2e6465'); }
  if (Adressat === 'MKV-PhX')                  { I_mehl = Decode('4d4b562d506858404d4b562d4d75656e6368656e2e6465'); }
  document.writeln('<A href="mailto:' + I_mehl + ( Betreff==='' ? '' : '?subject=' + Betreff ) + '">' + ( Text ==='' ? I_mehl : Text ) + '<\/A>');
}