Avaya's revenues climbed to $1.43bn (£698m) in the fourth quarter, a rise of five per cent and its highest figure in six years.

But the networking supplier's net profits totalled $35m, (£17m) a steep drop of 27 per cent on the $48m (£23.4m) collected in the same period last year. The company earned eight cents (four pence) per share in the quarter, compared to 10 (five pence) cents per share in 2006.

Final revenue for the fiscal year 2007 was $5.28bn (£2.58bn), up slightly from the 2006 figure of $5.15bn (£2.51bn). International sales benefited from the weak strength of the US dollar, according to the company.

Silver Lake Partners and Texas Pacific Group are expected to complete their acquisition of Avaya by the end of this month.