The ghost of Enron lives on.

It will be there when a US Senate sub-committee examines whether electronic energy exchanges should be subject to stricter rules. The problem goes back to 1993 when Enron lobbied the Commodity Futures Trading Commission (CFTC) to exempt electronically-mediated energy trading from government regulation.

At the time, Enron's push for deregulation was built around the premise that that investors who used its electronic trading platform were so sophisticated that they didn't need the same level of protection as investors in non-electronic exchanges. Of course, Enron's real agenda was total deregulation. It wanted to trade free of any supervision. Seven years later, it succeeded in getting up an exemption, known as the "Enron loophole," which was codified in the Commodities Futures Modernization Act. The result: a ridiculous two-tiered market, where one half is regulated and the other half not, a situation that resulted in the implosion of the hedge fund Amaranth last year.

As Salon's Andrew Leonard points out, this issue will have to be fixed as carbon trading becomes more prominent, especially with the likelihood that carbon will become the world's biggest commodity market.

"There is hardly an aspect of human existence on this planet that will not be affected by trading patterns in carbon markets," Leonard writes. "How energy is produced and consumed, how industry functions - the scope of such a market is so vast as to almost be beyond comprehension.

"The temptation to game and manipulate such markets will be irresistible. The responsibility of governments to regulate will be immense. The lessons of Enron and Amaranth must not be ignored."

There will only be one chance to get this right and fix it. And help bury Enron's legacy.