* Deadline extended to Jan. 16 (Adds details, background)

MILAN Dec 16 (Reuters) - Italian yellow pages group Seat Pagine Gialle said on Friday talks to restructure 2.7 billion euros ($3.5 billion) of debt would run into 2012 after it failed to win enough creditor support for a proposed deal by a Wednesday deadline.

It was the second time Seat, which defaulted in November, has extended the talks. The proposal includes the conversion of part of its debt into shares, strongly diluting its private equity owners CVC, Permira and Investitori Associati.

"The board has decided to extend to Jan. 16, 2012 the deadline for relevant stakeholders of the company to agree a consensual restructuring," it said in a statement.

The talks involve Seat's senior lenders, a group of about 70 banks led by Britain's Royal Bank of Scotland, and holders of a junior bond called Lighthouse.

Like other heavily indebted media companies, Seat was trapped in the credit crisis, which made it prohibitive to refinance while Internet competition strengthened and print advertising sales declined.

Similarly to Seat, talks over the debt of Endemol, the Dutch TV production company behind "The Big Brother", were extended this week to next year with a mid-February deadline.

Seat shares closed down 3.1 percent, giving the group a market capitalisation of less than 70 million euros. The stock has lost about 99 percent in value since its all-time 2007 peak.

Meanwhile, the Lighthouse bond was last bid at 8 percent of its face value, an all-time low.

($1 = 0.7665 euros) (Writing by Nigel Tutt; Editing by Helen Massy-Beresford)

• A Permanent Economic Emergency