Modify the custom error pages

Need the custom error pages working as SSI or PHP. Whenever I modify the following;

/etc/httpd/conf/vhosts/Vhosts_ispconfig.conf, this segment:

ErrorDocument 400 /error/error_400.shtml
ErrorDocument 401 /error/error_401.shtml
ErrorDocument 403 /error/error_403.shtml
ErrorDocument 404 /error/error_404.shtml
ErrorDocument 405 /error/error_405.shtml
ErrorDocument 500 /error/error_500.shtml
ErrorDocument 503 /error/error_503.shtml

and restart the webserver through ispconfig admin interface, the extensions are rewritten back to .html.

Anyone knows hot to prevent this? (Beside the onbvious "restart httpd through CLI", I don't know under what other circumstances it will get overwritten through other admin interface functions).

 

You'd have to modify /root/ispconfig/scripts/lib/config.lib.php.