Who said illegal trading on inside information is on the wane? The Securities and Exchange Commission, I have learned, has just kicked off an investigation into one of the year’s biggest financial deals – Bank of America’s $35 billion acquisition of MBNA Corporation, the world’s largest independent credit-card lender.

The focus is on last month’s domestic and foreign trading in both MBNA’s shares and options, notably in the period between June 6 and June 28. The transaction was announced shortly thereafter.

The SEC, as is usually the case, declined to comment, but a regulatory source confirmed the investigation, which is being handled by an enforcement attorney, Louis Gicale Jr., in the agency’s Washington office.

Surprisingly, I was not alerted to the probe by a news source, but rather by a reader, who I’ll call Jerry Ex (not his real name). Last month, Mr. Ex, who asked that his identity be withheld, bought his first stock, MBNA, in several years. He did so, he wrote to me in an e-mail, because his broker had told him of a rumor from a usually wired-in San Francisco trader that Bank of America (the country’s second-largest banking institution) would soon make a takeover bid for the credit-card company.

Lo and behold, within two weeks, on June 30 to be precise, Bank of America indeed made a bid – an offer equivalent to about $27.60 in cash and stock, based on MBNA’s previous day’s close of $21.07.

Not unexpectedly, the credit card company’s shares, based on a bid that represented a 31% premium from their June 29 close, ballooned on the news, surging that day about 25%. The stock is currently trading at $25.57.

Mr. Ex, of course, was delighted at the turn of events, that is, until his broker told him he had heard the SEC was investigating trading in the stock. His broker thought Mr. Ex had nothing to worry about, but suggested he play it safe by informing his attorney of the SEC’s involvement. His lawyer pretty much told him the same thing.

In an e-mail to me, Mr. Ex asked if I would check to see if he really was absolved of any wrongdoing. I checked with a securities lawyer, a former crack member of the SEC’s enforcement staff, who informed me that Mr. Ex, assuming he personally had no access to inside information, was home free. “Wall Street runs on rumors,” the lawyer said, “and there’s nothing illegal in trading on them.”

It’s unclear whether Bank of America and MBNA have been contacted by the SEC. Bank of America declined to comment, and MBNA did not respond to calls seeking comment.

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LIQUID GOLD: If you’ve got money to burn, read on. But you should know that one of our readers, Laurence Glasser, probably wouldn’t approve of your doing that. He made that clear in a recent e- mail in response to my July 6 column (“Potions for the Priviledged”) on the economics of after-dinner drinks in New York City restaurants. “Mr. D,” he wrote, “It is unfortunate you chose to wrote about such a flagrant abuse of wealth when there are so many starving people on this planet That you would discuss the idea of someone actually spending hundreds of dollars on an after-dinner drink is unthinkable. I am sure such drinks, your enthusiasm notwithstanding, are ultimately headed for extinction.”

The key drink featured in the column was what several top restaurateurs had told me was the city’s most expensive after-dinner thirst-quencher – a first growth 1863 Hardy Perfection, a 1.5-ounce shot of French cognac that ran $800 at Tse Yang, an upscale East Side Chinese dining spot.

Contrary to Mr. Glasser’s thinking, not only are pricey after-dinner drinks not becoming extinct, but they’re getting more expensive. Evidence of this is a new king on the block – a $900 shot of another Hardy Perfection cognac, which I was told about in an e-mail from a Bear Stearns managing director, Andrew Weiss.

The cognac, a blend that dates back a couple of hundred years, is being offered at Del Frisco’s, a midtown West Side steakhouse in the McGraw-Hill building, which is owned by Lone Star Steakhouse/Saloon, a Wichita, Kan.-based publicly held casual dining chain.

A Del Frisco’s bartender, Jonathan Heller, tells me, “We’ve sold a few drinks, especially to people who’ve gotten big bonuses. Some think it’s a great celebratory glass and they’re right.”