function UpdateBurger(pf)
{

	z = document.form.elements['fnBurgerlijkeStaatID'+pf];	
	a = z.options[z.selectedIndex].value; 	
	
	if ((a == 2) || (a == 4) || (a == 5)) 
		document.getElementById('enable2nd').style.visibility='visible'; 
	else 
		document.getElementById('enable2nd').style.visibility='hidden';

}