Russet, do you think the Malaysian flag is acceptable to use for the Malay language, wherever it's spoken?
I ask because it's also a national language for Indonesia, Singapore, and Brunei.
I agree with
Dane here, Singaporean has lots of national languages, all of which are represented by other countries (i.e. UK for English because they learn British English, China for Chinese, Malaysian for Malay, etc), so it probably isn't needed unless specifically requested. They learn standard Malay, so there isn't a noticeable difference between Malaysian Malay and Singaporean Malay.
Indonesian and Malaysian are
very different languages, they probably have similar roots in language, but I can only understand about 30% of spoken Indonesian since it borrows a lot of words from local languages like Javanese, Sundanese and Minangkabau, so I definitely think there should be a different flag for Indonesia.
On the other hand, Brunei Malay is more like a Malay dialect, so when I hear Brunei Malay it's like.. a Swedish person listening to a Danish person? A lot of the words sound similar so you can understand quite a bit if it's written down or spoken very slowly. There is still a marked difference though, so maybe the Brunei flag should be put on hold until someone from Brunei speaks up on the matter.