session problems with phplib

Sorry to post to dev group but the pear group is no longer active I can't get any answers to this problem anywhere so far. I'm sorta grasping at straws. I have a php script which is like a modified shopping cart. It starts with a search that calls a perl script ( I know, but it's the only way I can include certain proprietary functionality I need). This returns a results set of documents that can be either downloaded or requested depending on permissions. If you click to request a document a php script request.php is called it is sort of like a cart script, and uses phplib sessions and db_oci8. The strange problem I am having is this: If it is the first time you have reqeusted this script since last opening your browser, you will get a 404, if you hit back/forward or refresh the script works fine as if nothing ever happened. You will not get this error again as long as you do not close and reopen your browser. Any ideas? Here is the script "request.php" 62 lines, 1585 characters <? include ("layout.php"); page_open(array("sess" => "Repository_Session")); if (!isset($s)) { $s=0; }; $sess->register("s"); site_header("Request a Document - Document Cart"); echo '<P align=left><font face="Arial, Helvetica, sans-serif" size="2" color="#000066">Below is your <b><i><font color="#FF0000">Document Cart</font></i></b>.<br> <br> </font><font face="Arial, Helvetica, sans-serif" size="2" color="#000066">Any time you request a document we will store it here. You may <a href="http://starbase.msfc.nasa.gov/rs-bin/show_files.pl?search='.$s earch.'"> return to your search results</a> at any time and choose another document<br> or you may perform a <a href="search.php">New Search</a>.<br> <br> </font><font face="Arial, Helvetica, sans-serif" size="2">You may also Increase or Decrease the Number of copies you wish to request by using the <font color="#FF0000">Add/Remove </font>links, or completly empty the cart with the <font color="#FF0000">Clear cart</font> link.<br> <br> </font><font face="Arial, Helvetica, sans-serif" size="2" color="#000066">Whenever you are done selecting documents click the <i><font color="#FF0000">Checkout</font></i><font color="#FF0000"> </font>link to process your request.</font></P> <BR>'; global $scart; global $obj_id; $scart->start(); switch($action) { case add: $scart->add_item($obj_id,1); break; case remove: $scart->remove_item($obj_id,1); break; case clearcart: $scart->reset(); break; } $scart->show_all(); page_close(); site_footer(); ?>