Roman Catholic cardinals held a solemn Mass praying for divine inspiration on Monday, hours before locking themselves away from the world to elect a successor to Pope John Paul II. The Mass in St. Peter?s Basilica was led by 78-year-old German Cardinal Joseph Ratzinger, the Vatican?s doctrinal chief who is seen by some as a leading candidate for the papal throne.

?O God, eternal pastor who governs your people with the care of a father, grant your Church a pontiff acceptable to you for his holy life and entirely consecrated to the service of your people,? Ratzinger said in the opening prayer.

All of the 115 cardinal electors under the age of 80 who will enter the conclave joined older cardinals, bishops, priests, nuns and simple faithful in united prayer for the outcome of the conclave. The conclave, a unique election mixing ancient ritual with ultra-modern technology was due to start at about 4:30 p.m. (1430 GMT).

In a process dating back to medieval times, the ?Princes of the Church? will shut themselves in the Sistine Chapel and other restricted parts of the Vatican, emerging only when they have chosen the first new pontiff of the third Christian millennium and the 264th successor to St. Peter.

If the conclave resembles previous ones, the cardinals will need several days and repeated votes to reach a majority.

Whoever they choose will have to try to make his mark in the shadow of one of the most dynamic papacies in history.

?This is a very difficult papacy to inherit,? said Orietta Cristoferi outside St. Peter?s Basilica. ?He should have an openness to Latin America and other places. John Paul worked hard to open up to the whole world.? The conclave appears wide open with no sign of who will emerge as leader of the world?s 1.1 billion Roman Catholics. ?I believe the Holy Spirit already knows, but he hasn?t told us yet,? said Mexican cardinal Norberto Rivera Carrera.

<B>Divine influence</B>

Since John Paul?s death, media and bookmakers have tipped Ratzinger, the Dean of the College of Cardinals, as the early leader. Most Vatican experts doubt that Ratzinger, whose conservative dogma has polarised the Catholic world, will garner the two-thirds majority needed to become pope.

The cardinals, who will deliberate under Michelangelo?s masterpiece frescoes in the Sistine, will decide only after they are locked up whether to take a first vote yesterday night or wait today in the morning.

From today, they will vote as many as four times a day. Black smoke from a makeshift chimney on the Sistine Chapel will mark an inconclusive vote. White smoke and the tolling of St. Peter?s bells will mark the election of a new pope.

As in medieval times, the cardinals will be banned from communicating with the outside world, but the Vatican has taken new high-tech measures to ensure secrecy in the 21st century.

Mobile phones, newspapers, television, radio and the Internet will be banned. A false floor has been built in the chapel to accommodate electronic counter-bugging measures. Many say the new pope should be from the developing world.

Europe has only one quarter of the world?s Catholics but half the cardinals in the conclave. Italy controls the largest block, with 20 votes, but Italians were divided on whether the papacy should return to them after the Polish John Paul. ?I don?t care if he?s Italian or not, just as long as he?s a good man like the last one,? said Romano Mariozzi, a retired plumber from Rome.

The cardinal electors moved into a comfortable, specially built residence in the Vatican on Sunday night, an innovation some Vatican watchers believe could delay the vote.

Many times during past centuries until the last conclave in 1978, cardinals were locked in and around the Sistine Chapel.

The spartan environment was imposed to force a quick decision and avoid a repeat of a 13th century election that took almost three years. But 20th century elections have been short, none taking longer than five days. John Paul, an untipped outsider, was elected after eight ballots over three days in 1978.

Most Vatican experts expected another quick conclave, saying the white smoke would rise above the Sistine Chapel tomorrow evening or Thursday. They fear a long conclave would point to deep and dangerous divisions. ?From this evening, ideas will be clearer and (the cardinals) will be able to see the new pope emerging from the depths of the Sistine Chapel,? said Il Messaggero newspaper.

<B>PHILIP PULLELLA and Crispian BALMER</B>