// JavaScript Document
function cambia_imagen()
{	
	if(img_c=document.getElementById('img_val_form'))
		{
			casilla= document.getElementById('casilla_verif');
			if( casilla )
				casilla.value='';
			img_c.src="/pr/ap/imagen_valida_form.php?b="+Math.random();
		}
		
}