For what it's worth, the message is actually correct:
$ layman -i rostov
* rostov
* ~~~~~~
* Source : svn://os-rostov.ru/overlay
* Contact : oleg.kluchkin@gmail.com
* Type : Subversion; Priority: 50
*
* Description:
*
*
* Link:
*
* http://os-rostov.ru/
*
* *** This is no official gentoo overlay ***
*
$
i.e. the rostov overlay really doesn't have a "description" entry.

