Normally, you will have to translate them and re-certify them normally. I had mine accepted without translation because they were in Arabic and English.

You'd better make sure though before you do that. You say that your employer told you they "might" ask for translated copie! Well, ask him to confirm that and save you an unnecessary hassle in case they do not need translated diplomas.

By the way, it sounds like your employer is a government institution. If it is the case, get ready for more hassle and bureaucracy :)