Error Node no longer exists

[umount]

In log file I am have this is error

[12-Aug-2010 14:11:01] PHP Warning:  session_start(): Node no longer exists in /roundcubemail/program/include/rcmail.php on line 516                                                              
[12-Aug-2010 14:11:01] PHP Warning:  session_write_close(): Node no longer exists in /roundcubemail/program/include/rcmail.php on line 982                                                        
[12-Aug-2010 14:11:01] PHP Warning:  unserialize(): Node no longer exists in /roundcubemail/program/include/rcube_session.php on line 312                                                          
[12-Aug-2010 14:11:01] PHP Warning:  unserialize(): Node no longer exists in /roundcubemail/program/include/rcube_session.php on line 312                                                          
[12-Aug-2010 14:11:01] PHP Warning:  serialize(): Node no longer exists in /roundcubemail/program/include/rcube_session.php on line 222    

Version roundcube trunk.

[SKaero]

Its an XML error, is it happening with a fresh install?

[umount]

Its an XML error, is it happening with a fresh install?

thank you I am find error in my plugin.