I found a couple of places where some localizations are missing:
1. user-question: question/questions and answer/answer
2. the email sent to the user when a new answer is posted
For the user-question the solution was to copy the file to my template folder and edit it but I still don't know how to solve the email issue.
Update: In the settings I have a fully translated template for an email (which seems to be used for when a new question is posted) but then the email I got when a new answer was posted contains unlocalized portions:
From: "<email@example.com" <firstname.lastname@example.org>
Subject: [Perguntas do Abapinho] New answer on "Quem matou Moby Dick?"
Date: 16 April 2012 10:14:40 AM GMT+01:00
sdfraga adicionada nova resposta a Quem matou Moby Dick?:
Quem matou o Moby foi o Rock!
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