It seems Yahoo!Japan is not recognized as search engine by avast! WebRep.
Since Yahoo!Japan is the most major search engine in Japan, please support this.
Thanks for reporting this. We will add yahoo.co.jp shortly
I just noticed that yahoo.co.jp uses redirected urls which are not handled at the moment, stay tuned, we will be adding support for url redirectors soon
Thanks, much appreciated. 
Bump… :-\