NEW YORK, DEC. 17 -- Troubled developer Donald Trump surprised both his creditors and Wall Street today by coming up with $18.4 million in cash to make a debt payment and avoid plunging a second casino into financial crisis.

With just a few hours left before a midnight deadline, Trump said late this afternoon that he had made the interest payment to holders of the junk bonds that financed the Trump Castle, the biggest money-loser of his three hotel-casinos in Atlantic City.

In a telephone interview, Trump said that he made the payment because "I just thought it was the honorable thing to do."

The payment was unexpected because the Castle has not been raking in enough winnings to cover its debt. It had been widely predicted that Trump would default on the payment, which may have forced him to give bondholders an equity stake in the Castle. That's what happened last month, when Trump agreed to surrender 50 percent of the stock of the Taj Mahal after defaulting on interest due on that casino, his newest and biggest.

Holders of the Castle bonds were so sure that Trump would miss the payment due today that they already had hired lawyers and other advisers for what they anticipated would be lengthy negotiations to restructure the Castle's debt.

Nevertheless, there was still a widespread feeling among bondholders and in the financial markets that Trump had merely delayed the day of reckoning for the Castle until June, when he is due to make another large payment on the casino's debt. By then, Trump is likely to have to refinance the casino, a process that could force him to give up control, or possibly even sell the property, according to bond traders and other specialists.

"Unless Atlantic City turns around in the next six months, it {the payment} just buys him time until he can work out some kind of restructuring," said Mark Brostowski, a vice president in the high-yield group at Salomon Brothers Inc., an investment bank here.

But Trump insisted that his casinos were doing much better than the media has reported. When asked about the future, however, he declined to predict whether the Castle's situation would improve sufficiently by June.

Trump said the Castle had $18 million in cash on hand and that other Trump properties had "infused" additional money to make the payment.