It was only after Dana Calloway found himself sitting in a cell block rather than en route to freedom after pleading guilty to drug charges that the 21-year-old man realized he might have been duped by his partner.

That is when Calloway began the talking that led to the unusual acknowledgment yesterday by his partner, 23-year-old Alfred C. Jordan, that Jordan had convinced Calloway he probably would not go to jail if he lied and took full responsibility for selling cocaine to an undercover police officer.

Jordan yesterday admitted to D.C. Superior Court Judge Truman A. Morrison III that he attempted to get Calloway to plead guilty in their October 1985 arrests and to testify falsely that Jordan had not been involved in the sale.

With his attorney John Perazich standing by his side, Jordan pleaded guilty to distribution of cocaine and attempting to induce perjury. In exchange for his guilty pleas, the government agreed to dismiss an obstruction-of-justice charge.

The plan to encourage Calloway to lie came to light last January after Judge Robert S. Tignor ordered Calloway held at D.C. Jail pending sentencing on his two guilty pleas to selling cocaine. Calloway and Jordan, both of Fort Washington, Md., had been arrested after Calloway sold $50 worth of cocaine to an undercover police officer in the heavy drug trafficking area of Hanover Place. Shortly after the sale, police said, Calloway and Jordan were found holding the marked money.

Afraid that he might be spending a long time in jail, Calloway told his attorney about Jordan's plan, plotted during telephone calls and in letters to Calloway, who was to plead guilty and testify that he had given Jordan the marked money as payment for an unrelated debt. Jordan, he said, told him he was eligible for a special youth sentence that did not require the judge to impose the mandatory prison term for drug sales. Calloway was allowed to withdraw his guilty pleas after his attorney contacted the U.S. attorney's office and the judge. He later pleaded guilty to two misdemeanor drug possession charges in exchange for an agreement to testify against Jordan. Calloway is free pending sentencing.