Shibboleth breaks Apache error message formatting

[Jörg Knappen]

Hallo,

I have installed the newest Shibboleth Service Provider together with  
Apache-httpd 2.4.3.

The problem I encounter is that the nicely formatted error pages  
(e.g., File does not exist)
from Apache are broken now.

Apache's error log says:

(request for a non-existing page)

[Wed Feb 06 20:59:46.641816 2013] [mod_shib:error] [pid 1315:tid  
140341830469376] [client xxx.xxx.xxx.xxx:41988] shib_handler found no  
per-request structure
[Wed Feb 06 20:59:46.641857 2013] [include:error] [pid 1315:tid  
140341830469376]
  [client xxx.xxx.xxx.xxx:41988] unable to include "include/top.html"  
in parsed file /usr/local/apache2/error/HTTP_NOT_FOUND.html.var

I searched both the Shibboleth and Apache httpd mailing list archives,  
but I didn't find a clue to this one.

Yours,

Jörg Knappen