I'm trying to send an email with some conditions to several partners (mass_mail: True). My email template is the next one:

% if object.is_friend:
    Hello my friend.
% else:
    Hello.
% endif

When I click on the preview of the template, I see the result perfectly. In fact, if I send the mail from the form of a partner, he receives the email with the right content.

The problem is when I try to send the mail from the tree view of partners (where mass_mail is True), because the selected partners receive an empty mail.

I updated the branches of addons and server (OpenERP7). But no result in this point. Can anyone help me, please?