Hi,
If you go on new "Admin EMail Manager" interface then open it..
then click on the differents menu on top:
SMTP Quarantine | SMTP Spool | SMTP Log | POP3 Quarantine
one after one without stopping until you reach web admin supposed timeout, it will effectivelly timeout and close whereas there is still activities (as u keep clicking on the menus on top)
to reproduce this reduce your web admin idle timeout to 60 secs and just cycle-click on the 4 menus (not the close of course[:)] )
thx