[imp] Viewing none existing message

[Teo.Fan]

Hi,
when I view none existing message, I get errors:

Notice: Undefined index: 1 in
/usr/local/apache2/htdocs/horde/mail/message.php on line 271

Warning: Cannot modify header information - headers already sent by (output
started at /usr/local/apache2/htdocs/horde/mail/message.php:271) in
/usr/local/apache2/htdocs/horde/mail/message.php on line 515

Notice: (null)(): Mailbox is empty (errflg=1) in Unknown on line 0


Please suggest me how to show friendly message.
thanks and regards,

Teo.Fan