function isFilled (passedField, pMessage) {
    var str = passedField.value;
		if (str == ""){
			alert(pMessage);
			passedField.focus();
			return false;
    }
    return true; 
  }
 
  function isNum(passedField, pMessage){   
    var str = passedField.value;
  	if (str == ""){
      alert(pMessage);
      passedField.focus();
      passedField.select();
  		return false;         
  	}   
  	for (var i = 0; i < str.length; i++){
  		var ch = str.substring(i, i + 1);
  		if ((ch < "0" || "9" < ch) && ch != '.'){
  			alert(pMessage);
        passedField.focus();
        passedField.select();
  			return false;         
  		}      
  	}   
  	return true;   
  }

  function isChecked (passedField, pMessage) {
		if (! passedField.checked){
			alert(pMessage);
			passedField.focus();
			return false;
    }
    return true; 
  }
  
	function validEmail(passedField, pMessage) {
    var str = passedField.value;
		invalidChars = " /:,;";

		if (str == "") {
			alert(pMessage);
      passedField.focus();
      passedField.select();
			return false;
		}
		for (i=0; i<invalidChars.length; i++) {

			badChar = invalidChars.charAt(i);
			if (str.indexOf(badChar,0) != -1) {
  			alert(pMessage);
        passedField.focus();
        passedField.select();
				return false;
			}
		}

		atPos = str.indexOf("@",1);
		if (atPos == -1) {
			alert(pMessage);
      passedField.focus();
      passedField.select();
			return false;
		}

		if (str.indexOf("@",atPos+1) != -1) {
			alert(pMessage);
      passedField.focus();
      passedField.select();
			return false;
		}

		periodPos = str.indexOf(".",atPos)

		if (periodPos == -1) {
			alert(pMessage);
      passedField.focus();
      passedField.select();
			return false;
		}

		if (periodPos+3 > str.length)	{
			alert(pMessage);
      passedField.focus();
      passedField.select();
			return false;
		}

		return true;
    }


	function validEmailOptional(passedField, pMessage) {
    var str = passedField.value;
		invalidChars = " /:,;";

    // accept blank values, but non-blanks must be valid email addresses

		if (str == "") {
			return true;
		}
		
		return validEmail (passedField, pMessage);
		
    }