CORRECTED-Italy probes Saint-Gobain plasterboard activities

(Corrects product type to plasterboard from cartonboard in headline and quote)

MILAN, March 10 (Reuters) - Italy's antitrust authority has launched an investigation into Saint-Gobain's (SGOB.PA) Italian unit over possible abuse of its dominant position in the nation's plasterboard market, the watchdog said Tuesday.

The Saint-Gobain PPC Italia unit was told of the investigation during inspections carried out on Tuesday, by Italy's financial police, into Saint-Gobain putting up possible obstacles for rivals to enter the market.

"The investigation has been launched after a complaint from a company that told of notable difficulties it met in attempts to set up ... a plant for production of plasterboard in order to launch operations on the Italian market," the authority said in a statement.

The probe will check whether the Saint-Gobain unit's behaviour prevented a new market entrant, it said.

In 2007, the unit had sales of 150 million euros, the authority said.

The authority has until March 31, 2010, to complete its investigation, it said. (Writing by Nigel Tutt; Editing by Andrew Macdonald)