GLOBAL MARKETS-Euro hit by debt worry, stocks fall on techs

* Ireland turns spotlight back onto euro zone debt

* Disappointing Cisco outlook weighs on Wall St

* Gold erases gains as dollar strengthens (Updates with European markets' close)

By Walter Brandimarte

NEW YORK, Nov 11 (Reuters) - The euro fell to a five-week low on Thursday on concerns about Ireland's ability to repay its debt while earnings fears knocked U.S. stocks lower after a technology bellwether gave a dismal earnings outlook.

Gold erased initial gains as the dollar rose against major currencies. Oil prices were little changed, with news of strong Chinese demand offset by the rise of the greenback.

Yields on 10-year Irish bonds rose to a record high over comparable German debt as investors speculated Ireland will soon need financial help to service its debt. For details, see [ID:nLDE6AA0MK].

Ireland's Finance Minister Brian Lenihan admitted the surge in borrowing costs had become "very serious," but European officials denied for a second day that Dublin was seeking financial aid -- echoing the denials heard six months ago when Greece needed an EU/IMF bailout.

"Europe never fully addressed these problems, and it's clear solvency issues in Ireland have not been resolved," said Marc Chandler, global head of currency strategy at Brown Brothers Harriman, who sees the euro at $1.33 by the end of 2010.

The euro fell as low as $1.3642, a five-week low, and was last down 0.89 percent at $1.366. It also posted losses against the yen and hit a seven-week low against sterling .

"The euro can't sustain even modest upticks right now, and a fall below $1.3650 could open up another two-cent decline," Harriman added.

The dollar strengthened against major currencies, with the U.S. Dollar Index <.DXY> up 0.69 percent. Also supporting the greenback was a U.S. think tank report saying the Federal Reserve may scale back its latest plan to buy government bonds.

Against the Japanese yen, the dollar was up 0.21 percent at 82.46.

Europe's woes diverted attention from a G20 summit in South Korea, where major rich and developing countries tried to hammer out an agreement to reduce global economic imbalances and avoid competitive currency devaluations. [ID:nTOE6AA0BQ]

TECH WEIGHS ON WALL ST

Technology shares led a slide on Wall Street after a disappointing outlook from Cisco Systems Inc . [ID:nN10245398]

The Dow Jones industrial average <.DJI> fell 90.44 points, or 0.8 percent, to 11,266.60, while the Standard & Poor's 500 Index <.SPX> lost 8.17 points, or 0.67 percent, to 1,210.54. The Nasdaq Composite Index <.IXIC> was down 28.67 points, or 1.11 percent, at 2,550.11.

Cisco's shares fell more than 15 percent after Chief Executive John Chambers expressed caution about short-term challenges in Europe and purchases by public-sector customers.

European stocks ended little changed, with investors cautious about the situation in Ireland. The FTSEurofirst 300 <.FTEU3> index of top European shares provisionally edged 0.03 percent lower after falling 0.7 percent on Wednesday. The index is up 71 percent since a record low in March 2009 but only 6 percent higher in 2010.

"It's time to book profits, that's what we're doing. The market is ripe for a correction," said Jean-Yves Dumont, head of asset allocation strategy and funds at Dexia Asset Management, which turned "underweight" on equities on Wednesday.

Gold prices were slightly up in volatile trade, with the strength of the greenback taking off some of its shine. Prices for the metal rose 0.2 percent to $,1405.90 an ounce. U.S. crude oil was practically unchanged at $87.86 a barrel.

The U.S. bond market was closed for Veterans Day. (Additional reporting by Edward Krudy and Steven C. Johnson in New York, Blaise Robinson in London; Writing by Walter Brandimarte; Editing by Kenneth Barry)