David Kreinberg quit Comverse earlier this year

David Kreinberg, former finance boss, admitted wrongdoing and agreed to help prosecutors with their investigation.

Mr Kreinberg and former chief executive Kobi Alexander are among those accused of illegally pocketing millions of dollars by abusing share options.

Mr Alexander was recently arrested in Namibia after an international manhunt.

'False statements'

He is currently on bail there awaiting extradition proceedings to the United States.

Prosecutors claim Mr Kreinberg, Mr Alexander and company lawyer William Sorin boosted the value of their share options by exercising them at a point in the past when the firm's shares were worth much less.

I agreed with the chief executive and others at the company to assist them in continuing the practice David Kreinberg, former Comverse finance director

Prosecutors claim the three men hid this practice - known as 'backdating' - from other board members and Comverse's accountants.

They are also alleged to have falsified financial statements and ultimately pocketed more than $8m, with Mr Alexander taking $6.4m.

Appearing before a Federal Court in New York City, Mr Kreinberg acknowledged that his actions were "wrong".

"The company was in fact issuing backdated options with an exercise price lower than the fair market value on the grant date," he said.

"After learning this, I agreed with the chief executive and others at the company to assist them in continuing the practice."

Out in Africa

Mr Kreinberg, who is due to be sentenced in February, faces a maximum of 15 years in jail.

Mr Alexander, who has dual US and Israeli citizenship, has been charged with 32 counts of alleged conspiracy, fraud and money laundering in relation to abuse of share options.

He was detained in Namibia in August after allegedly fleeing the US earlier in the year.

Media reports have suggested that Mr Alexander intends to plead not guilty to the charges.

The US does not have an extradition treaty with Namibia and legal experts have said extradition proceedings are likely to take some time.