I didn't even know it was closed for Malaysia, and in fact I even doubt it. Except if it comes from Malaysia governement, otherwise I see no reason for adsense not being open for malaysia publishers.
Adsense is worldwide as far as I know, except for a few high risk countries. Malaysia is definitely not one of them.
you can actually check on the list of the languages allowed- http://support.google.com/adsense/bin/answer.py?hl=en&answer=9727 However, i saw many site in Malay are approved by adsense since it is similar to Indonesian languages