Amir Taheri: What Gives?

He apparently is the source for the National Post story about Jews being forced to wear yellow badges in public in Iran. The Post has now retracted the story, but I haven't found any explanation from Taheri. The FT reports:

The Post story was drawn from a column in the paper by Amir Taheri, editor of the state-owned Kayhan newspaper under the Shah of Iran before the 1979 Islamic Revolution. Mr Taheri claimed the law was 'drafted two years ago' and had been revived 'under pressure' from President Mahmoud Ahmadi-Nejad.
'The new codes would enable Muslims to easily recognise non-Muslims so that they can avoid shaking hands with them by mistake, and thus becoming najis (unclean),' Mr Taheri wrote.
A contributor to various newspapers including the New York Post, the Wall Street Journal and Al-Sharq Al-Awsat, a leading Arabic-language newspaper, Mr Taheri is an opponent of talks between the US and Iran.
He wrote in the New York Post last month the US should 'go for regime change in Tehran' as the only way to stop Iran's drive to 'dominate the region and use it as the nucleus of an Islamic superpower which would then seek global domination'.

I've long read Taheri and appreciated his columns and reporting. All I can say is: he owes everyone an explanation. How did he come up with this? Was it a garbled misunderstanding? Was it propaganda? After the Iraq WMD debacle, we need to treat all intelligence from interested parties in the Middle East with a great deal of skepticism. The tragedy is: the underlying fact of Ahmadinejad's anti-Semitic extremism is true. Which is why sloppy MSM journalism can only help Iran's leadership, rather than harm it.