Object lifetime

I'v got CLASS 1 and CLASS2. CLASS1 makes many instanses of CLASS2 and stores them in an array. Ex. ---------------------------------- load class definition... start_session(); <html> <form typ...... <?PHP $cl1=new CLASS1; ---------------- I serialize CLASS1 into a $_SESSION['cla1'] ->submit form -> and unsreialize it to same var $cl1=unserialize($_SESSION['cla1']); $cl1 is operational with same data as before 'submit form'. I can change values of data in $cl1. I CAN read/print data in the instanses of CLASS2 that $cl1 created before 'submit form'. I CAN NOT change the data in the instanses of CLASS2 that $cl1 created before 'submit form'. mark I'v only serialized CLASS1. Is this at all possible ?? I'v find it strange since I can use/print the data that is stored in CLASS2 before 'submit form'. regards Roger Helgesen