Did Richard Shelby Spout Security Secrets?

I know, I know. It's only fashionable to discuss Sandy Berger, but:

The Justice Department has referred to the Senate Ethics Committee an investigation into whether Sen. Richard Shelby of Alabama or his staff leaked classified information, indicating that criminal charges are highly unlikely, a federal law enforcement official said Saturday.

The referral Thursday means that it is now up to the ethics panel to decide if any action is warranted against Shelby, a Republican who was vice chairman of the Senate Intelligence Committee at the time of the Sept. 11, 2001 terror attacks.