In fact in my php.ini at /etc/php.in is already defined to "America/Sao_Paulo"
When I use mail client such as windows mail the e-mail messages get right time/hour.
Is there anyway to know wich php.ini the horde is using? Would be the same that I have at /etc/php.ini?
In meantime when I go to global configurations at horde the time is been displayed correctly but when I got to inbox the hours is at least 3 hours minus then the expected.
I have found it at: /etc/psa-webmail/horde/horde/php.ini
and the timezone is correctly configured. I do not have any ideas whereelse to check to fix this. It is annoying and a lot of people complaining about this problem in their webmail.