Stocks were poised to open higher Friday as Spain worked on reform measures in anticipation of a bailout package and as Apple debuted its latest iPhone worldwide.

Spain is considering freezing pensions and speeding up a planned rise in the retirement age as it races to cut spending and meet conditions of an expected international sovereign aid package, Sources with knowledge of the matter said.

"The problems are very big (in Spain and Europe in general), it's possible this is the beginning of the workout of the situation, it certainly takes some pressure off," said Rick Meckler, president LibertyView Capital Management in New York.

"But you can expect - as it's gone on all year - there will be positive and negative news stories out of Europe until Germany makes some firm decision on its level of commitment."

After gaining about 6 percent since the start of August, largely on expectations for new economic stimulus measures by world central banks, the S&P 500 <.SPX> has seen muted action this week. The index has been unable to muster a daily move of more than 0.4 percent in either direction in the wake of the Federal Reserve's latest quantitative easing plan.

There may be increased volatility towards the close Friday due to 'quadruple witching' - the quarterly settlement and expiration of four different types of September equity futures and options contracts. Expiration can lead to greater volume and volatility as players adjust or exercise their derivative positions.

"That has historically been a positive day for the market so you have some people just really looking at that," said Meckler, referring to the quadruple witching.

Minneapolis Fed President Narayana Kocherlakota, who has long argued that pushing too hard to get Americans back to work risks inflation, reversed course and suggested the Fed should keep rates low until the jobless rate drops to 5.5 percent.

Apple Inc will be eyed as the company's iPhone 5 hits stores around the globe, giving the consumer giant a boost ahead of the crucial end-of-year holiday season, even as rival Samsung Electronics Co <005930.KS> steps up its legal challenge over key technologies. Apple shares advanced 0.7 percent to $703.65 in premarket trade.

Oracle Corp gained 2 percent to $32.90 in premarket trading after the software maker posted first-quarter earnings that met Wall Street expectations but said hardware sales are expected to drop further after tumbling 24 percent from a year ago.

S&P 500 futures rose 5.5 points and were above 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 gained 55 points, and Nasdaq 100 futures added 12.25 points.

Michael Kors Holdings Ltd rose 4.3 percent to $54.75 in premarket trading after the company said it will likely earn more than it earlier expected in the second quarter as the fashion and accessory designer banks on strong global sales.

Darden Restaurants Inc posted first-quarter earnings that beat analysts' estimates, and the company stood by its sales and profit forecast for the year. Shares rose 3.8 percent to $56.80 premarket.

Vivus Inc plunged 13.3 percent to $20.56 after the company said it expects a European committee to recommend against the approval of its obesity drug Qsiva, based on preliminary feedback from the committee.

(Editing by Bernadette Baum)