function eCheckEMail(sn){
    s= sn.value;
    if (s.indexOf("@") == -1) return false;
    if (s.indexOf(".") == -1) return false;
    at=false;
    dot=false;
    for (var i = 0; i < s.length; i++) {
        ch = s.substring(i, i + 1)
        if ((ch >= "A" && ch <= "Z") || (ch >= "a" && ch <= "z")
                || (ch == "@") || (ch == ".") || (ch == "_")
                || (ch == "-") || (ch >= "0" && ch <= "9")) {
                if (ch == "@"){
                  if (at) return false;
                  else at=true;
                }
                if ((ch==".") && at)
                   dot=true;
        }
        else return false;
    }
   return dot;
}

function CheckEMail(theForm){
   for(var i=1; i<CheckEMail.arguments.length; i++)
      if(theForm.elements[CheckEMail.arguments[i]].value!="") {
         if (!eCheckEMail(theForm.elements[CheckEMail.arguments[i]])){
            alert("O E-mail informado parece inválido! Favor verificar.");
            theForm.elements[CheckEMail.arguments[i]].focus();
            return false;
         }
      }
   return true;
}

function CheckRequiredFields(theForm)
{
   for(i=1; i<CheckRequiredFields.arguments.length; i++)
      if(theForm.elements[CheckRequiredFields.arguments[i]].value=="" ||
         theForm.elements[CheckRequiredFields.arguments[i]].value==0 ){
         alert("Um campo requerido não foi informado. Favor preenchê-lo!");
         theForm.elements[CheckRequiredFields.arguments[i]].focus();
         return false;
      }
   return true;
}

function CheckForm(theForm){
  if(!CheckRequiredFields(theForm,0,6,8))
     { return false; }
  if(CheckEMail(theForm,6))
     { return true; }
  return false;
}