function validate_required(field,alerttxt)
{
	with (field)
	{
		if (value==null||value=="")
			{return false;}
		else {return true}
	}
}

function validate_email(field,alerttxt)
{
	with (field)
	{
		apos=value.indexOf("@");
		dotpos=value.lastIndexOf(".");
		if (apos<1||dotpos-apos<2) 
			{return false;}
		else {return true;}
	}
}

var error_messages = new Array();

function validate_form(thisform)
{
  var valid = true;
  var error_str = "";
  for (var i = 0; i < thisform.elements.length; i++) {
    var name = thisform.elements[i].name;
    if (name.match(/_req$/)) {
      if (!validate_required(thisform.elements[i])) {
        valid = false;
        if (error_messages[name]) {
          error_str += error_messages[name] + "\n";
        } else {
          error_str += name.substr(0,name.length - 4) + " is required\n";
        }
      }
    } else if (name == 'email_from') {
      if (!validate_email(thisform.elements[i])) {
        valid = false;
        if (error_messages[name]) {
          error_str += error_messages[name] + "\n";
        } else {
          error_str += "Please enter a valid email address\n";
        }
      }
    }
  }
  if (valid) {
    return true;
  } else {
    alert(error_str);
    return false;
  }    
}