The ISEQ Index recovered some ground this afternoon to close 36 points lower at 5,912 after more heavy falls in financial and telecom stocks.
With the US market closed today for Presidents' Day the European telecom sector caused the most anxiety after rumours hit the market of a major restructuring at Vodafone.
Eircom was hard hit by negative sector sentiment and the news that IL&P and Enba had pulled out of three way partnership in developing an Internet bank.
Eircom fell 13 cents to euro 2.43, IL&P shed 22 cents to euro 12.85.
Bank of Ireland slumped by 18 cents to break the 10 euro barrier today closing at euro 9.99. AIB, which is due to report results on Wednesday fell 4 cents to 12.10.
Ryanair fell 30 cents to euro 12.15 today. The low cost airline denied media reports that it had decided on Carleroi in Belgium as its European hub.
Exploration company Tullow annouinced a positive report on its Yorkshire gas operation. Tullow shares gained 2 cents to euro 1.20.
London's FTSE 100 index managed to claw its way back from earlier losses today, with gains for old economy sectors outweighing losses for troubled telecoms stocks.
But Vodafone limited the FTSE rally with its 3.2 per cent decline following the uncertainty surrounding the company's planned sale of Infostrada to Enel.
With oil prices slightly higher, oil stocks benefited. BP Amoco was up 2.3 per cent, Shell was 1.3 per cent higher and in the FTSE 250, Enterprise Oil added 0.6 per cent.
GlaxoSmithKline, the pharmaceuticals group, was up 2 per cent on expectations it will on Wednesday announce substantial cost savings from its recent merger.