function validate_listform(thisform)
{
	with (thisform)
	{
		if (!validate_required(firstname,"Please enter your First Name."))
  		{
  			return false;
  		}
		if (!validate_required(lastname,"Please enter your Last Name."))
  		{
  			return false;
  		}
		if (!validate_email(email,"Not a valid e-mail address!"))
  		{
  			email.focus();return false;
  		}
	}
}

function validate_required(field,alerttxt)
{
	with (field)
	{
		if (value==null||value=="") {
	  		alert(alerttxt);return false;
	  	} else {
	  		return true; 
	  	}
	}
}
function isNumber(strValue){
     if(isNaN(strValue)){
          alert("Please enter a valid number!");
          return false;
     }
     return true;
}
function validate_email(field,alerttxt)
{
	with (field)
	{
		apos = value.indexOf("@");
		dotpos = value.lastIndexOf(".");
		if (apos<1||dotpos-apos<2) 
		{
			alert(alerttxt);return false;
		} else {
			return true;
		}
	}
}
function validate_radio(btn,alerttxt)
{
    var cnt = -1;
    for (var i=btn.length-1; i > -1; i--) {
        if (btn[i].checked) {cnt = i; i = -1;}
    }
    if (cnt > -1) {
		return true;
	} else {
  		alert(alerttxt);return false;
	}
}
function enableOther(field)
{
	fieldname = document.getElementById(field);
	fieldname.disabled = false;
	fieldname.focus();
}
function disableOther(field)
{
	fieldname = document.getElementById(field);
	fieldname.disabled = true;
}