US STOCKS-Futures ease after Japan data, Greece meetings eyed

* Dell slashes full-year outlook

* Japan export data weak

* UPS extends offer period for TNT

* Futures down: S&P 4.2 pts, Dow 31 pts, Nasdaq 8 pts

By Edward Krudy

NEW YORK, Aug 22 (Reuters) - U.S. stock index futures eased on Wednesday as weak export data from Japan underscored the headwinds facing the global economy, while Greece was beginning a series of meetings with European officials aimed at securing more time to push through reforms.

Japan's exports slumped the most in six months in July as shipments to Europe and China tumbled, adding to concerns over global demand after a string of dire trade figures from Asia's export engines.

"Japan's numbers were terrible, their exports to Europe just disintegrated," said Paul Mendelsohn, chief investment strategist at Windham Financial Services in Charlotte, Vermont. "The Japanese numbers confirm what we already know - that Europe and China are slowing down."

Greek Prime Minister Antonis Samaras starts a European charm offensive with talks to persuade euro zone chief Jean-Claude Juncker that the debt-laden nation has the will to ram through unpopular reforms and deserves more time to do it. 

Stocks have rallied over the summer partly on signs of strength in the U.S. economy and partly on the belief that the European Central Bank will act to prop up the euro zone. The Japanese data, while not undermining that thesis, did sound a note of caution.

S&P 500 futures fell 4.2 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures fell 31 points, and Nasdaq 100 futures lost 8 points.

Toll Brothers Inc, the largest luxury homebuilder in the United States, reported a higher quarterly profit and a sharp jump in new orders amid a recovery in the housing market. The shares rose 3.4 percent.

Dell Inc - The No. 2 U.S. PC maker - warned of a challenging second half and slashed its full-year earnings outlook as customers cut back on computer purchases ahead of the launch of Microsoft's Windows 8 software. Dell's shares fell 5.2 percent.

The S&P 500 hit a four-year intraday high on Tuesday before reversing gains and finishing in negative territory in a sign the index could struggle at these higher levels without new catalysts. Some investors are also worried about the potential for a swift reversal as has happened in the recent past.

"Is something going to happen over the next couple of days or weeks that continues this pattern we've had that every time we get up to this level it's not sustainable," said Mendelsohn.

European shares fell on Wednesday. Cyclical stocks led the decline on growth concerns fueled by the weak export data from Japan. But expectations of more stimulus measures by central banks capped losses. The FTSEurofirst fell 0.8 percent.

The euro fell to a session low against the dollar as some investors took profit on the single currency's rally to a seven-week high the previous day.

United Parcel Service will extend the offer period for Dutch rival TNT Express to Nov. 9 because antitrust conditions will not be met before the original deadline of the end of this month.

Shares in Sunrise Senior Living rose 60 percent to $14.20 after Health Care REIT Inc said it would acquire the company for $ 14.50 per share.

Japan posted an 8.1 percent annual fall in exports, far deeper than economists' median forecast of a 2.9 percent drop. A 25.1 percent plunge in exports to the struggling European Union, the biggest such drop since Oct 2009, saw Japan post a record trade deficit with the region.