BY TERE FIGUERAS

  A Cuban family of three found floating in the Florida Straits last week with eight others in a converted Buick ''car-boat'' cannot be returned to the island before Wednesday, a Miami federal judge said Monday.

  U.S. District Judge Federico A. Moreno heard arguments from lawyers with the exile group Democracy Movement, who asked the court to halt the repatriation of Luis Grass Rodríguez and his wife and child.

Moreno extended his emergency injunction -- which he granted on Friday to prevent the Grass family's repatriation over the weekend -- for another two days, allowing
government attorneys time to file a written response to a question of jurisdiction.

Immigration officials have not decided the fate of the Grass family, Assistant U.S. Attorney Dexter Lee told the judge.

The other eight Cubans, including four children, ''could be repatriated within 24 hours,'' Lee said.

  The Grass family -- husband Luis, wife Isora and their 4-year-old son, Angel Luis -- were singled out because the father was the only one of the Buick migrants who had been granted political asylum hearings with the U.S. Interest Section in Havana, said attorney William Sánchez. Grass was in the middle of the process when he grew frustrated and left.

  Another difference between Grass' case and that of his fellow Buick passengers: Sánchez said the government's own records showed the group was picked up 25 miles off the Keys. At some point, the group was divided and the Grass family was on a separate cutter that took them inside the 12-mile U.S. territorial limit.

  Neither the U.S. Coast Guard nor the State Department has commented on the case of the Buick's 11 passengers, citing policies of not addressing pending cases.

  Under the U.S. immigration policy known as ''wet foot/dry foot,'' Cubans who are interdicted at sea are generally sent back to the island, while those who make it onto U.S. soil are allowed to stay.

  Sánchez and his fellow attorneys on the case argue that certain protections should apply to migrants who make it into American waters.

  Lee argued that another federal judge as well as an appeals court had maintained mere presence in territorial waters was not enough.

  The Grass family and another man aboard the Buick -- fellow mechanic Marcial Basanta López -- were among a group of Cubans who tried a similarly venture last year aboard a 1951 Chevy pickup outfitted with makeshift pontoons and a propeller.

  The Chevy was intercepted about 40 miles from Key West, sunk by machine-gun fire and its occupants sent back to Cuba. All but two of the Chevy's 12 riders were
  immediately denied visa applications. Grass and another man were given interviews with the U.S. Interest Section. Basanta and the rest were sent letters rejeting their
  requests. In court, Moreno expressed his admiration for those who masterminded both ventures, while acknowledging the court's limitations on intervening.

  The judge expects to make his decision by 5 p.m. Wednesday.