ovgrouppat in inn.conf

[Mirek Luc]

In my inn-BETA-20000612 it doesn't work at all. If ovgrouppat==anything
(some pattern, true, false...) I get "Can't write overview <...>: Bad file
number" from overchan or "cant store overview for <token>" from innd. 
Of course groupbaseexpiry is set to false. Any ideas?
BTW, man inn.conf says:
     ovgrouppat
         If set, restricts the overview data stored by INN to
         only the newsgroups matching this comma-separated list
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
         of wildmat expressions.  Newsgroups not matching this 
[...]
         overview data will fail.  This is a boolean value and
                                             ^^^^^^^
         the default is false.

-Mirek