Registering an Array in a Session

Hi, I am trying to register an array in a session, but am having no luck. What I have is a form with set fields on which is processed a certain number of times. Upon submitting the form each time, I run the following: session_register("fieldtext[".$page."]"); where fieldtext is the name of a field on the form, and $page is the page number, which increases by one each time the form is submitted. All I get registered is the last value submitted on the form, all the previous values are null. Any advice would be most appreciated. TIA Alexis