// Start of generic navigation functions
           
    function back() {
        history.go(-1);
    }
	
	// advance user to next field automatically
	function check_next(thisfield,nextfield,flength) {
	    if (thisfield.value.length == flength) {
	        eval("document.form." + nextfield + ".focus();");
	    }
	}
		    
	// End of generic navigation functions