I user google translate but I supervise every translations, I mean that they have tools for edit po files and they suggests translations for every term and you could also use keyboard shortcuts to make it quickly by moving between terms to be translated, backward or forward and accept the suggested translation. For example I use this url for access the po translation toolkit

https://translate.google.com/toolkit/

Nobody will be able to use OpenERP or anything else if it is translated by Google Translate or any other automatic translation system. Do your users a favor and offer true translations or no translations.