Shares of S1 ( SONE) were among technology's losers Monday, falling 10% after the software company announced a restructuring plan and warned that third-quarter results would fall below expectations.

S1 expects to report a loss of 9 cents to 10 cents a share on sales of $57 million to $58 million. The loss forecast includes an estimated $3.5 million in charges related to the reorganization plan, which includes cutting 8% of the company's workforce and consolidating some facilities. The company said the plan is expected to reduce annual operating expenses by $20 million to $22 million. S1 plans to record charges totaling $14 million to $15 million over the third and fourth quarters related to the moves.

The company now expects its financial institutions segment to report total third-quarter sales of $47 million to $48 million. Previously, S1 had predicted it would post total sales of $61 million to $64 million and financial institutions sales of $53 million to $55 million. Excluding charges, the company expects its financial institutions segment to post a loss of 4 cents to 5 cents a share, worse than its prior projection for break-even results to a loss of 3 cents a share. Analysts polled by Thomson First Call projected loss of 1 cent a share on sales of $63.3 million.

RSA Security ( RSAS) fell 6% after the company narrowed its third-quarter forecast. The company, which makes digital security products, expects to report third-quarter earnings of 20 cents to 22 cents a share, including a benefit of 8 cents to 9 cents a share related to tax refunds. Previously, the company projected it would earn 11 cents to 14 cents a share, before any tax gains. RSA also narrowed its sales estimate to $76 million from a range of $74 million to $78 million. Analysts project earnings of 12 cents a share on sales of $75.8 million. RSA will post full third-quarter results on Oct. 27. Shares were trading down 69 cents to $11.51.

Shares of Nortel Networks ( NT) rose 7% after the company said that its chief operating officer, industry veteran Mike Zafirovski, would succeed Bill Owens as chief executive Nov. 15. Nortel said that Zafirovski is "the right leader to build on the important work of Bill Owens -- and take Nortel to the next level." Over Zafirovski's 30-year career, he served in a number of positions at General Electric ( GE) and Motorola ( MOT). Shares of Nortel recently traded up 23 cents to $3.53.

Overland Storage ( OVRL) rose 2% after the data-storage company expanded its share repurchase plan. The company is now able to repurchase up to 2.5 million shares without a maximum dollar limit, which, at current prices, would represent about $20 million in stock. Previously, Overland had been authorized to purchase up to $10 million in stock. "The board of directors believes that the current share price of Overland common stock does not reflect the intrinsic value of the company," the company said. Shares were trading up 14 cents to $8.03.

Shares of Anteon International ( ANT) fell 2% after the information-technology services company said it acquired privately held Milestone Group for $31.5 million. Milestone, which recorded sales of roughly $21 million for the 12 months ended Sept. 30, is expected to boost Anteon's earnings but, given the timing of the deal, isn't expected to increase the company's earnings during 2005. Shares of Anteon were trading down $1.03 to $42.01.

Other technology movers included Lucent Technologies ( LU), up 12 cents to $3.18; Microsoft ( MSFT), down 16 cents to $24.51; Oracle ( ORCL), up 18 cents to $12.49; Intel ( INTC), up 3 cents to $23.26; Cisco ( CSCO), down 2 cents to $17.25; Apple Computer ( AAPL), down $1.08 to $52.92; Sirius Satellite Radio ( SIRI), up 2 cents to $6.19; Sun Microsystems ( SUNW), down 3 cents to $3.95; Applied Materials ( AMAT), down 1 cent to $17.32; and SanDisk ( SNDK), up 41 cents to $50.85.

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