[Koha] Koha email question.

[Juszczak]

Hi all
I have question, does koha can sent automatic mail to patrons when books 
on hold is avainable?
I mean  patrons reserve books, and when it become available, he got 
message.
Or another situation, patron check out books, and in two days he must 
return or renew it.
He got mail please return or renew item/books.
It is posible? If yes when i can start find option to config/set up this.?