What's floating around now is that the al-Qaeda presence in Iran is in some manner aided by rogue elements in the Iranian Revolutionary Guard. After Iraq I'm just a little skeptical of the whole "intelligence sources" line, but this is plausible, and if so could be even more disturbing than if the Iranian government were behind things.

The IRG is the same segment of the Iranian armed forces which is said to be generating terrorism in the Occupied Territories by smuggling through Hizbullah. (This is probably the most recent example.) A bit of googling suggests they - and especially the al-Quds Division - might be the key to Iran connections to terrorism, and I see a lot of quotes in that direction from the Saudi Arabian newspaper ash-Sharq al-Awsat. However, that may not mean that even the hard-liners in Iran's government are behind this, as I've long been curious about their relationship with the the most extreme elements in Iran. Three years ago, there was an alleged "crisis committee" within the IRG which drew up plans for a coup against President Khatami. (One surviving link from then is here.) The most interesting thing is that getting the support of Ayatollah Khamanei was a step in the plan, which implies strongly that these "senior officials" in the IRG were not acting in concert with him, despite the fact he is officially in charge.

I would be very interested in reading a current report on the IRG and their links with both the Iranian government and terrorism. It may be that there are really three power blocs in Iran - the reformist camp led by President Khatami, the post-Khomeini conservatives led by Ayatollah Khamanei, and the militants in the IRG and elsewhere. What that means for Iran's internal political battles is uncertain.