Support phorum email notifications - without +1

Hi,
I use your support phorum, create new support questions (feature requests) and subscribe to email notifications to new posts on this questions.
There is option to unsubscribe from all new posts.
But there is no option to unsubscribe "+1" posts only.
I like "+1" posts but I don't think it is necessary to receive email notifications like "new post +1 from XY". And there is no way to filter it in Gmail because filter ... message has "+1" ... matches for all messages with word "1".
Thanks,
Jiri