Michael Jackson, the Jew

Roseanne Barr - possibly not the world's most reliable source - has written a note to Michael Jackson's children:

You are jewish, and your dad really loved jewish people and considered himself one of them. He considered that it didnt matter if a person was black or white, rich or poor, Muslim or christian, but that it DID matter if a person was jewish. Your dad believed that the Jewish People would change the world just by changing themselves. This is a very important jewish concept! Your dad would want you to know these things, he was a student of kabballah. kabballah teaches us that the jews need to change themselves, and to do that, they need to accept that they came from africa, from ethiopia, and not from europe!"

If Michael Jackson considered himself such a Jew, how come he converted to Islam?