The chairman of telecommunications company Stentor, Mr Dan O'Neill, resigned yesterday, just four days before its a.g.m. More management changes are expected, according to sources close to the company.

It follows the resignation of finance director Mr Cormac Lucy earlier this month. Just one week ago the ailing company was thrown a lifeline by an existing shareholder who pledged fresh funding of £5.5 million. The company has accumulated debts of £14 million.

There was considerable surprise earlier this year when Stentor, had to inform the London Stock Exchange that its Mr O'Neill had sold 75,000 shares. A statement to the LSE said Mr O'Neill had charged the shares to his bankers "in contravention of covenants contained in the placing agreement" between Mr O'Neill, Stentor and its nominated advisers.

Mr O'Neill told the company that sales of the shares took place without his knowledge and therefore could not be notified. Stentor, whose chief executive is former minister Mr Conor Cruise O'Brien's son Patrick, has seen its share price plummet from a high of £1.95 sterling to 3.5p at one stage. Yesterday the shares closed at 12.5p.

The company's a.g.m will be held in Dublin on Tuesday. It is expected that the remaining executives will be closely questioned on Stentor's performance.