ZURICH (Reuters) ? Reinsurer Converium dumped its chief executive yesterday, saying it wanted a fresh start with a new man at the helm after a turbulent 2004 in which it was forced to ask investors for more cash just to survive.

Eager to try to regain the trust of investors, Converium said it had appointed board member Terry Clarke to take over from Dirk Lohmann.

Last year, it uncovered a $481.1 million shortfall in reserves that forced it to ask shareholders for $420 million in fresh cash. The saga wiped two thirds off its market value.

"The board believed it was necessary to put the past behind, and start a new life with a new CEO," a company spokesman said. "At this point in time continuity and strong leadership are crucial for Converium."

Analysts said the news was long overdue, and suggested it may herald more changes when it reports full-year 2004 earnings on Tuesday. "It's certainly good news ... it sounds as if there could be be further restructurings," said Georg Marti at ZKB.

Analysts warned that the initial relief rally in its shares would be short-lived, as the market had already priced a change in CEO into the shares, which have risen by over 11 percent so far this year.

Analysts attributed the shares' fall to the fact that investors had started to fret that more trouble over reserves may be ahead.

The timing of the change in leadership, so close to its annual results next Tuesday, has stoked speculation that the company may add more cash to its troublesome claims provisions, analysts said.

"Reading the statement closely, I'm somewhat afraid there could be new negatives in the pipeline. We're keeping the stock's rating at underperform," said Frank Stoffel at WestLB.

"The first things (Clarke) might do is to plug any remaining hole in reserves so he can start with a clean slate," said Lehman Brothers Insurance Team.

Converium is also looking for a new finance chief and earlier this month appointed an interim CFO to fill in when finance chief Martin Kauer leaves at the end of this month.

The company has widely been viewed as a takeover target since its reserve troubles. Its difficulties in swiftly dealing with its management issues have added fuel to such speculation.

One London-based analyst said of the appointment of the 63-year old Clarke: "To my mind, this cannot be a permanent appointment and Converium is therefore without a long-term CEO or CFO." He added: "We would usually take this as a signal that the company's in play ? but who's going to take the risk?"

In a brief statement Converium said Clarke would take over as CEO with immediate effect and that the company would now focus on creating a leaner structure.

"The board believes that a management change is necessary to bring about a long-term cultural transformation and restore stakeholder confidence in the company," Converium's Chairman Peter Colombo said in the statement.

Clarke joined the Converium board in 2002 and was named as managing director in September, 2004, which sparked growing speculation that Lohmann's days at Converium were numbered. But Converium had repeatedly denied that a CEO change was planned.

Converium had ranked among the ten largest reinsurers in the world, but its business is expected to halve this year after credit rating cuts and the closure of its large US unit.