Robert a thirty-something living in the San Francisco bay area, is glum. His plans for an initial public offering of his dotcom company have just fallen through. To make matters worse, shares he acquired under stock options issued by his previous high-technology employer have plunged 96 per cent.

He had hoped to use them to pay for a new floor for his house. Now they will buy only a piece of furniture - a nice one, it is true, but a piece of furniture none the less.

Similar hard-luck stories are becoming increasingly common as share prices slide, particularly in the technology and telecommunications industries. Stock options that many workers hoped would make them rich now appear worthless. As a result, many who flocked to companies that offered potentially high rewards through stock options have now begun to leave.

But the danger of a serious brain drain has now prompted technology and telecoms companies to look again at their stock options. Indeed, many have started to tinker with them in ways that could bring their workers a big pay-off after all.

Sprint, the US telecoms company, was one of the first to act, offering workers the chance to swap their old, worthless options for new ones that are likely to have a better chance of making them money. Its shares had fallen nearly 70 per cent from their high point, leaving employees with options that are deeply "underwater": the current share price is far below the price employees would have to pay to exercise the options.

Many other companies are looking at ways of changing the terms of their options plans. Such moves are likely to bring a backlash from other shareholders, who must take their losses on the chin when share prices fall. The sight of a company's workers - and particularly its senior executives - being bailed out after a share price slide has become one of the things that most angers big institutional shareholders.

They have plenty of reason to be annoyed when companies react too quickly to big swings in share prices. Two years ago E*Trade, the online broker, slashed the exercise price on its employee options after its shares tumbled from $30 to $8 in a general stock market slump. Within two months, though, the shares had bounced back above $30, eventually reaching $60 - implying a big windfall for E*Trade workers thanks to the lower exercise price.

With the company's shares now back under $16, Christos Cotsakos, E*Trade's chairman, sounds far more circumspect about the idea of repricing. "Certainly, if a stock drops disproportionately to everyone else, (options) become a big issue," he says.

A near-50 per cent share price decline at National Service Industries, an Atlanta-based company that makes lighting, chemicals and envelopes, has left virtually all of its options underwater, says Jim Balloun, chairman. He says he has no intention of repricing, though: while some employees in the finance department have moved on, most managers are unlikely ever to leave companies where they have spent their whole careers.

"We hate it," says Mr Balloun. "But we don't think they will be underwater for ever."