Is the Iranian Revolutionary Guard Corps cracking?

Is the Iranian Revolutionary Guards Corps (the Pasdaran in Farsi) starting to turn against the mullah regime? There have been hints for some time; now comes another:

In an act of open subordination, during the March 10th demonstrations in Tehran, seven members of the Iran Revolutionary Guard Corps (IRGC) security forces refused to shoot at protesters on the streets. Arrested and jailed in Tehran’s infamous Evin prison for interrogation, they are still being interrogated as the Iranian regime’s authorities debate how to deal with them.
During the interrogations the regime’s intelligence sources have repeatedly warned the seven — identities still unknown — that they must reveal the names of the “leaders” of the organization(s) they are taking orders from, as well as disclose the names of any other member of the IRGC and Basij forces working undercover.
To that end, the commanders of the Basij have joined the interrogators and are absolutely determined to make the connection between the insubordinate guards and the authors of a recent letter written to Mohammad-Ali Jafari, the chief commander of the Revolutionary Guards. The open letter, published at various sites, was penned by a number of top-ranking but anonymous members of the IRGC. In it, they announce their defiance of their orders and their refusal to treat protesters with violence.
The accused reject all knowledge of such a letter.
The commanders of the IRGC are said to be debating the proper form of disciplinary action. Where a few have suggested that firing them would be just punishment, the majority are reluctant to consider letting it go at that, certain that any and all those who refuse to follow orders must be severely punished.
But execution does not seem to be an effective deterrent. Back in August 2010, a number of the IRGC members who were arrested and detained for insubordination were drugged and then buried alive. But, of course, the news didn’t stay under wraps for very long. Soon enough, it was widely reported by blogs and human rights organizations.
[...]
With the blessings of the supreme leader, Jafari has begun to set up a task force to investigate and counteract the further spread of dissent in the ranks. The task force will be comprised of handpicked members of the Quds Force and its mission is twofold: first, to send undercover members of the IRGC or Basij to infiltrate dissenting groups, and, second, to publicize and discredit the subversives in order to discourage further defections.
It is said that in a private meeting with Khamenei, Jafari expressed his fear of a domino effect within the region given the influence of recent events throughout the Middle East and North Africa upon his ranks. Jafari stressed that news of the Libyan pilots who fled Libya in a fighter jet for Malta and the defections of other Libyan military personnel could reverberate throughout the Iranian military and trigger similar actions.

For the past few years there have been persistent reports of Arabs being used as militia troops -- not Pasdaran and not Iranian military, but in the Basij and other assorted militia -- to maintain government control over the seeting Iranian populace.  As you might know, Arabs are not Iranians or vice versa, and the two groups generally do not like each other, a factor that has played a large role in limiting the influence of the Iranian mullahs in the Arab world. 

Given this background, the use of Arabs in the Iranian security forces suggests two things:

1. The mullahs cannot trust the Persians in their own Pasdaran or army; and
2. The Arabs are more receptive to the message of the Iranian mullahs than the Iranian people are.

This incident reinforces the first point.  The second point is dangerous juxtaposition for not just the mullahs but for the US, seeing as how the Muslim Brotherhood is starting to take power in Arab Egypt.