Scrolling down to section B -
4B. For the purposes of this Law, "Jew" means a person who was born of a Jewish mother or has become converted to Judaism and who is not a member of another religion."
Looks like the law was amended in 1970 to include converted Jews as well. I don't see anything in the law about conversion needing Orthodox approval but I certainly could be wrong. Alouette, any thoughts?
Never mind, I see you basically answered the question already. :) Makes sense.
For many years the Chief Rabbinate had to approve all conversions, making sure that they were performed according to halachah. From the time this law was adopted there has been an effort to add the words according to halachah to all conversions.
Non-Orthodox demoninations have complained that their converts are "discriminated against" but opponents of non-Orthodox conversions maintain that there should be only one standard for conversion--allowing non-Orthodox conversions is a guarantee there will be no standards.
Reform or Conservative conversions done outside of Israel are recognized, but remember you don't have to be Jewish to be eligible under the right of return.