Hope Thiago is your firstname? Thanks for showing your interest in helping out with the translations. I just checked the por-BR translation file in Linguist and all words/strings are indeed 100% translated.
That does not say you are not welcome of course, to help maintain the translation. I'm also looking for help in the Dutch translation for example. I could not verify myself if anyone on the list (http://projects.ez.no/ezpublish_translation/team/members) is from Brazil and supplied that translation, I know it was submitted to Nicolas (community manager) directly.
If I can help in any way, put you in touch with the current translator(s), do let me know.
Regards Robin
Board member, eZ Publish Community Project Board - Member of the share.ez.no team - Key values: Openness and Innovation.
I think there's already some people from Brasil, thanks anyway. I could help translate to Dutch, but it's like an alien language to me and my keyboard, sorry.