U.S. stock index futures pointed to a weaker open on Wall Street Wednesday, with futures for the S&P 500, the Dow Jones and the Nasdaq 100 down by between 0.3 and 0.4 percent.

* At 1215 GMT, Automatic Data Processing releases its September employment report. Economists expect 75,000 jobs were created in September.

* The Institute for Supply Management releases at 1400 GMT its September non-manufacturing index. Economists forecast a reading of 52.9 versus 53.3 in August.

* The Mortgage Bankers Association releases at 1100 GMT Weekly Mortgage Market Index for the week ended September 30. The mortgage market index read 767.9 and the refinancing index was 4,239.6 in the previous week.

* At 1130 GMT, Challenger, Gray & Christmas releases its report on job cuts for September. Challenger reported 51,114 layoffs in August.

* The U.S. Environmental Protection Agency is expected to ease a new air pollution rule that would require power plants in 27 states to slash emissions, The Wall Street Journal reported, citing people familiar with the matter.

* Sprint Nextel said it will sell the next version of Apple's iPhone, ending months of speculation about whether it would become the third U.S. operator to sell the popular device.

* Asian smartphone makers have a chance to exploit a rare letdown from Apple after the new iPhone 4S failed to wow fans and investors, leaving Android rivals better placed to grab market share.

* EU regulators will formally object this week to the planned merger of Deutsche Boerse and NYSE Euronext , two sources with knowledge of the case said, which may force the companies to offer concessions to ease competition concerns.

* Oil and gas firm Anadarko Petroleum Corp said the resource potential in the Offshore Area 1 of Mozambique's Rovuma Basin had increased.

* Bank of New York Mellon was sued on Tuesday by New York federal and state prosecutors who accused the bank of cheating clients in foreign exchange transactions.

* European shares rose in early trade, led by banks after European finance ministers agreed to safeguard the region's lenders. The FTSEurofirst 300 <.FTEU3> index of top European shares was up 1.3 percent.

* Japanese stocks gave up early gains and ended lower, with the broad Topix index hitting its lowest level since the March earthquake. The Nikkei average <.N225> fell 0.9 percent.

* Investors rushed in to buy U.S. technology and other beaten-down sectors as the S&P 500 dipped in and out of a bear market on Tuesday, before a late rally drove the index to its largest gain in more than a week.

* The Dow Jones industrial average <.DJI> gained 153.41 points, or 1.44 percent, to 10,808.71. The S&P 500 <.SPX> gained 24.72 points, or 2.25 percent, to 1,123.95. The Nasdaq Composite <.IXIC> gained 68.99 points, or 2.95 percent, to close at 2,404.82.

(Reporting by Atul Prakash; Editing by David Holmes)