With the noises from Congress growing louder, Wall Street says it’s getting the message. Top executives are “in discussions to possibly cap their own compensation,” the Wall Street Journal reports.

Of course, these talks don’t come unprompted. Rep. Henry Waxman (D-CA) recently requested information about what the first nine banks participating in the Treasury Department’s capital injection program (getting $125 billion in total) plan for this year’s bonuses. Potentially even more worrisome for the banks, New York Attorney General Andrew Cuomo recently requested the same information. Cuomo has already threatened legal action against AIG for excessive exec bonuses.

But if recent history has taught us anything, it’s that Wall Street can be quite innovative. And while execs may be discussing curtailing annual bonuses, the Journal also reports that the firms owe their executives billions through other means, such as deferred pay and special executive pensions.

The sums, compiled by the Journal because they are usually not reported, can be staggering: $11.8 billion at Goldman Sachs, $8.5 billion at J.P. Morgan Chase, $10 billion to $12 billion at Morgan Stanley, and around $5 billion at Citigroup. In the case of Goldman, that sum vastly exceeds its $399 million pension plan for employees.

The executive goody bags, says the Journal, “are like 401(k) plans on steroids.” The execs defer bonuses or salary into an account, which can sometimes be matched by the employer – and sweetened on top of that with a healthy interest rate:

Often, it is a generous rate. At Freddie Mac, executives earned 9.25% on their deferred-pay accounts in 2007, regulatory filings show—a better deal than regular employees of the mortgage buyer could get in a 401(k). Since all this money is tax-deferred, the Treasury, and by extension the U.S. taxpayer, subsidizes the accounts.

These bonuses are especially relevant for two reasons. First, because the bailout rules, which place some restrictions on executive pay, don’t affect this type of compensation. And second, because a number of firms don’t set aside assets to cover these expenses, departures by top execs can hit a firm’s balance sheet when it doesn’t expect it.

It’s unclear whether the recent inquiries by Waxman or Cuomo will touch on these types of bonuses. Certainly anything is possible. In this new era of government investment in Wall Street, executives are learning a new sensitivity to public perception. As one corporate watchdog told Bloomberg, “They are just a bonus away from having the villagers come after them with torches.”

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