... As change comes slowly but surely to culture of Wall Street.

THE head trader at an investment bank wanted a tryst with a prostitute. Eager to please, two employees of a securities firm that was wooing his bank booked him a room and a woman.

This was back in the days when a woman's place on Wall Street was clear.

"That's just how the Street works," the two employees explained when they listed the hotel bill as a business expense.

That's not how the firm works, responded their boss, who was (uh-oh!) a woman.

So ended those guys' employment at Muriel Siebert & Co., Siebert said, recalling the incident from 25 or 30 years ago.

That small evolutionary turn in "how the Street works" occurred because of another evolutionary bump: A woman was in charge of a Wall Street firm. Siebert became a first when she bought a seat on the New York Stock Exchange in 1967.

Change begets change.

It's still unusual for a woman to be in charge of much on Wall Street, which is precisely why the men in charge have to worry about the law. Actually, they should have been worrying about the law for 40 years.

Congress outlawed job discrimination based on race, religion, gender and nationality in 1964. Still, women are filing cases like the one Morgan Stanley paid $54 million to settle in federal court in Manhattan.

The case began as a complaint by Allison Schieffelin, a former bond seller who had worked in Morgan Stanley's institutional equity division for 14 years, ultimately earning more than $1 million a year. Now 42, she has said she loved the firm and she loved her job.

Schieffelin wanted to work her way into becoming a Morgan Stanley managing director. Year after year she was passed over. She came to believe that all that stood between her and the promotion was her gender.

Morgan Stanley denies that.

Yet, this was a place where women were barred from firm-sponsored gatherings with clients at strip bars and golf weekends, where an in-house birthday cake might resemble a breast and where women complained of being groped, according to allegations filed in court.

When Schieffelin took her complaint to the federal Equal Employment Opportunity Commission, she was fired. Morgan Stanley cites other causes, namely, insubordination. The EEOC said her dismissal was retaliation and therefore illegal.

The judge impaneled the jury, but wouldn't you just know it? By the time lawyers had culled through the pool of contenders, they wound up with four men and EIGHT women.

(Here's a note about another change. Not until 1957, 37 years after women won the right to vote, did Congress pass a law saying federal courts had to let women sit on federal juries. State courts could still bar women from injuries, the U.S. Supreme Court ruled in 1961. Finally, in 1975-1975!--the court ruled that states, too, had to let both genders into jury boxes.)

So, here we are, in 2004, in federal court in New York with a jury of eight women and four men poised to hear a store of women testify about men behaving badly at Morgan Stanley.

The firm figured it was time to settle.

Change begets change.

The settlement is "generating a good deal of interest" beyond Morgan Stanley, says Donald Livingston, a former EEOC general counsel and now a Washington-based partner in Akin Gump Strauss Hauer & Feld.

Financial services firms he represents have been calling him to ask what the EEOC claimed, what constitutes a "pattern and practice" case, how do such cases get tried and how could they avoid being subjected to such a suit.

Does this mean the case will surely lead to a sea change on Wall Street? Livingston isn't sure. "It's a sharp-elbows, high-octane, pretty intense environment," he says. It's "difficult to get high-achievers to conform to rigid workplace requirements."

Siebert says some elements of Wall Street culture--the long hours, competition and heavy travel--won't change and that women, like men, must accept these terms or find other work.

She does see change in that part of the culture that demeans women and keeps them out of the top jobs. "A lot of firms are treating women right, and those that aren't are going to get a little afraid" because of the Morgan Stanley case, she says.

Cultures don't change automatically.

"It has to change because there's a decided effort made by the people on top," Siebert says. "When that happens, it will open a lot of things. Slowly, but surely."

Ann Woolner is a columnist for Bloomberg News.