* Francis makes first address to entire Vatican administration
* The Curia was dogged by allegations of dysfunction
By Philip Pullella
VATICAN CITY, Dec 21 (Reuters) - Pope Francis on Saturday told Vatican administrators, who were dogged by infighting and allegations of corruption during the papacy of his predecessor, to be humble professionals and "conscientious objectors" to gossip.
"When professionalism is lacking, there is a slow drift downwards towards mediocrity," Francis said in his first Christmas greetings to the members of the Roman Catholic Church's central administration, known as the Curia.
He told the cardinals, bishops, monsignors and lay people who work in the various Vatican departments that administer the 1.2 billion-member Church that they should always strive for "professionalism and service".
When he was elected in March, Francis inherited a Curia in disarray and still reeling from the "Vatileaks" scandal, in which documents stolen from former Pope Benedict's office alleged corruption and petty infighting among monsignors.
Benedict, who became the first pope in 600 years to resign, was also tainted by reports in the Italian media of a so-called "gay lobby" in the Curia that used blackmail against others.
Prelates in the Curia were also known to use Italian journalists to spread rumours or anonymously attack members of different factions in the bureaucracy.
Francis was elected with a mandate to reform the Catholic Church's central structure, and named an international commission of eight cardinals to advise him on what changes to make.
In his address, he said he wanted the Curia to turn a page.
"Holiness, in the Curia, also means conscientious objection to gossip," he said, and, departing from his prepared speech, added that there were also "saints" working in the Vatican.
In October, the eight cardinals advising the pope said they believed the Holy See's central government needed a total overhaul to fix it.
They have advised the pope that the Vatican needs a new constitution to govern the workings of its various departments, to replace the existing one written in 1998.
Bishops around the world have criticised the Curia for being heavy-handed, autocratic, condescending and overly bureaucratic, and some accused it of reflecting the trappings and intrigue of a Renaissance court.
Francis has said previously that one main problem of the Curia was that it was too focused on its own interests.
Francis has sought to bring openness, consultation and humility to the Vatican. He has shunned the spacious papal apartment and lives in small quarters in a guest house.
His decision to take advice from the cardinals - from Italy, Chile, India, Germany, Democratic Republic of Congo, the United States, Australia and Honduras - is a sign that he intends to take seriously calls from within the Church to decentralise a traditionally top-heavy institution.
Before resigning, Benedict left a secret report for Francis on the problems of the Curia, which were exposed when sensitive documents alleging corruption were stolen from his desk by his butler and leaked to the media.
There have been suggestions that some Vatican departments should be merged and others closed in order to make the Curia more efficient and to prevent corruption.
This week the Vatican said it had engaged an international consulting firm to make sure all the Vatican's departments, including those accused in the "Vatileaks" scandal, met international standards of financial accounting. (Reporting By Philip Pullella; editing by Mike Collett-White)
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