Richard Bentley in his update to v1.3 of
his Register Globals Patch Files makes
a change in both the admin and catalog
sessions.php file to the function
link_session_variable.  This is what
he says about the change:

"Function : link_session_variable()
The $nothing variable ought to be
initialised (this can cause warnings
to be issued on some PHP installations)"

If you need to make the change this
is what he refers to:

// Unmap global from session variable (note that the global variable keeps the value of
      // the session variable. This should be unnecessary but it reflects the same behaviour
      // as having register_globals enabled, so in case the OSC code assumes this behaviour,
      // it is reproduced here
      $nothing;

IS CHANGED TO:

// Unmap global from session variable (note that the global variable keeps the value of
      // the session variable. This should be unnecessary but it reflects the same behaviour
      // as having register_globals enabled, so in case the OSC code assumes this behaviour,
      // it is reproduced here
      $nothing = 0;
      
      
Rhea (Vger)