Advanced Guestbook - Error - please help

Hi,

I have the following problem: If I want to add a comment to an etry I get this message:

Warning: Cannot add header information - headers already sent by (output started at /mnt/ls2/06/372/00000001/htdocs/seite/gb/comment.php:5) in /mnt/ls2/06/372/00000001/htdocs/seite/gb/lib/comment.class.php on line 175

But the comment is added.

And the second is similar like this. After I have embedded the guestbook in the site and login as the admin I get this message:

Warning: Cannot add header information - headers already sent by (output started at /mnt/ls2/06/372/00000001/htdocs/seite/gb/admin.php:6) in /mnt/ls2/06/372/00000001/htdocs/seite/gb/lib/admin.class.php on line 33

Warning: Cannot add header information - headers already sent by (output started at /mnt/ls2/06/372/00000001/htdocs/seite/gb/admin.php:6) in /mnt/ls2/06/372/00000001/htdocs/seite/gb/lib/admin.class.php on line 34

Warning: Cannot add header information - headers already sent by (output started at /mnt/ls2/06/372/00000001/htdocs/seite/gb/admin.php:6) in /mnt/ls2/06/372/00000001/htdocs/seite/gb/lib/admin.class.php on line 35

Warning: Cannot add header information - headers already sent by (output started at /mnt/ls2/06/372/00000001/htdocs/seite/gb/admin.php:6) in /mnt/ls2/06/372/00000001/htdocs/seite/gb/lib/admin.class.php on line 36

What is wrong? 8O And how I can correct this? Could anyone help me please?
Thanx

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