WASHINGTON (CNN) -- A judge said Thursday he will delay setting a possible trial date for a former State Department analyst and his wife on charges they spied for Cuba because their lawyers need security clearances to see the potential evidence.

Justice Department prosecutors insist on security clearances for the defense team before they can review classified evidence the government says it has compiled against Kendall Myers and his wife, Gwendolyn.

U.S. District Judge Reggie Walton asked them whether it was correct that they wished to allow a delay pending a status hearing set for November 20.

"Yes it is," said Gwendolyn Myers, who in court papers is also identified by prosecutors as Agent 123.

"That's correct," affirmed Kendall Myers, also known as Agent 202 by the prosecution.

The hearing began more than 30 minutes late because of delays bringing the Myerses to the courthouse from a detention facility. They entered the courtroom wearing matching prison clothing, and both seemed relaxed as they smiled at their attorneys.

But because they would face spending the rest of their lives in prison if convicted, they are considered a flight risk. A judge at an earlier hearing rejected a request that they be freed pending trial.

The couple pleaded not guilty in June to a five-count indictment, and have insisted they be tried together before a jury. They are charged with conspiracy to act as illegal agents of the Cuban government, wire fraud and providing classified information to Havana, according to court documents.

Prosecutors claim Kendall Myers, 72, was recruited by the Cuban Intelligence Service in 1978 after he returned to the United States from a trip to Cuba.

In the years that followed, he landed jobs at the CIA and then the State Department, where he held a "top secret" security clearance. He retired in 2007.

Prosecutors say the case against the couple includes allegations of low-tech intrigue such as getting secret messages from Cuba on a shortwave radio.

"Found by their bed in their apartment during a court-authorized search was the shortwave radio they described" to the undercover investigator, prosecutors wrote. "They received Morse code shortwave radio messages from Cuba on that radio," purchased with money from the Cuban Intelligence Service, the court documents allege.

They have been in custody since their June 4 arrest by the FBI at the end of an undercover investigation. In court papers, the government says it has a compelling case against them, using their own words recorded by the FBI.

As recently as April, the government says, the Myerses told an undercover agent "their plan for escape from the United States to Cuba, which they referred to as 'home,'" and that "they were going to sail there on their sailboat," which is docked at a marina near Annapolis, Maryland.

The couple planned a trip next week, according to an entry for November 9 in a personal calendar prosecutors said the FBI seized from Kendall Myers during his June arrest.

There are no entries after that date, according to the prosecution's court filing.

In June, a neighbor who lives on a sailboat near the one owned by the Myerses told CNN that they had mentioned taking a trip to the Caribbean late this year.

Prosecutors quote Gwendolyn Myers as saying they would live on that sailboat once they made it to Cuba "so that they -- in her words -- 'wouldn't be a burden' to the Cubans," according to government documents.

U.S. District Judge Reggie Walton has a difficult challenge ahead of him: deciding how to protect sensitive U.S. intelligence while ensuring evidence is available for the Myerses to receive a fair trial.

Walton faced the same challenge over classified documents as the trial judge in the "leaked spy" case against former Vice President Cheney's chief of staff, Lewis "Scooter" Libby.