It displays the following messages:

Fatal error: Call to undefined function: page_open
() in /home/webmail/docs/horde/imp/mailbox.php3 
on line 89

and 

Fatal error: Call to undefined function: page_open
() in /home/webmail/docs/horde/problem.php3 on 
line 78

when clicking the !problem? link.

Hope this helps and you are able to fix the 
problems sometime shortly. Also, has the spam or 
block sender functions been created as previously 
mentioned in one your replies to a post?

Thank you and good luck fixing the problems! ^_^