Don't know whether this is a netscape or a gnome bug, but if you click on the buttonbar from the bottom right hand corner of communicator to turn it into a window, you get an entry in the pager winlist. So far, so good. Minimising this window sends the window back to the buttonbar, but it's entry still appears on the pager.
This seems to be an enlightenment/gnome-pager bug. I will forward it to the GNOME mailing lists.