function ValidateForm(thisform) 
{
	var cLB = "\n"; // creates a line break; 
	var thisFormName = thisform;
 	var cFirst_Name = "";
	var cLast_Name = ""; 
	var cEmail_Address = ""; 
	var cPhone_Number = ""; 
        
	if (document.forms[thisFormName].exchange_firstName.value.length == 0) cFirst_Name= "First Name" + cLB;
	if (document.forms[thisFormName].exchange_lastName.value.length == 0) cLast_Name = "Last Name" + cLB;
	if (document.forms[thisFormName].exchange_email.value.length == 0) cEmail_Address = "E-Mail Address" + cLB;
	if (document.forms[thisFormName].exchange_phone.value.length == 0) cPhone_Number = "Phone Number" + cLB;


	// Build string for alert:
	cBase = cFirst_Name + cLast_Name + cEmail_Address + cPhone_Number;
		
	// Display an alert if any of the input is missing:
	if (cBase.length > 0)
	{
		alert("Please fill out your:" + cLB + cLB + cBase);
		return false;
	}
	else
		return true;
        
}