How to install Hebrew on a Samsung galaxy s vibrant

We have a Samsung Galaxy S vibrant, bought in the US from T-mobile. It's unable to read text messages in Hebrew, write in Hebrew, or anything else. We tried to install the language through the languages section in the settings, but we couldn't find an option for Hebrew. We tried to install a language pack through the market, but it didn't work. How can we install full support for Hebrew? The phone is Samsung Galaxy S vibrant, bought from T mobile in USA (NYC). firmware version is 2.1 with update 1.