Soft-spoken and somewhat media-shy, Mr Tom Montgomery doesn't fit easily into the smug public image of many of Ireland's growing clutch of new economy entrepreneurs. In person, he exudes neither Denis O'Brien's magnetic presence nor Cyril McGuire's bustling energy. Rather, in common with many Ulstermen, Mr Montgomery displays a down-to-earth attitude and an awareness of the merits of thrift and hard work.

And despite founding three of Northern Ireland's most successful software companies - Kainos, Lagan Technologies and Amacis - he drives to work in a 10-year-old Renault and is barely known in his native Belfast. But all this is destined to change as Amacis, the firm he founded just last year, takes the world by storm with its flagship product Amacis Visibility, and establishes itself among the island's top software companies.

"Traditionally, communications involved only phone calls, but now companies are getting millions of requests or inquiries though e-channel communications," says Mr Montgomery. "Our product provides our customers with a complete communications solution through several channels," he says. "It can deal with e-mails, Internet chat and short messaging services from mobile phones." The customer relationship management software developed by Amacis is complex and works on several levels. At basic levels it detects the identity of a sender of communication, checks its authenticity and later decodes the information. But it also offers corporations a selection of more detailed value services. Visibility can translate a communication into 30 different languages and has the ability to understand and prepare outline responses to communications. To cap all this, it can evaluate the skills of customer representatives in directing individual communications to the most relevant person at the most suitable geographical location.

Sounds impressive, but is all this really necessary? Judging by the rapid growth in the number of deals Amacis is concluding, leading corporations seem to think so.

Later today the company will announce a deal with the German insurance corporation, HUK-COBURG. It will use Amacis software to manage the incoming e-mail and Internet messages from its 6.5 million customers at 400 customer services offices. This success follows a major contract in August when Amacis signed HSBC, one of the world's largest banks, as a customer. Despite the concentration of financial services customers, Amacis's core product targets almost all market sectors, listing media corporations, airlines and electrical utilities among its customers.

The company may also be close to breaking into the lucrative US market. It is understood a major deal with a US corporation is currently being signed off and could be announced as early as the new year.

"If you are serious about being a major player, you have to be in the US market," says Mr Montgomery. "We would lose credibility if we did not compete there."

Mr Montgomery is pushing hard in the region. Amacis opened a sales and administration headquarters in Boston last month and is seeking US venture capital backers as part of a £10 million sterling (€16.67 million) funding round due to be announced shortly.

"We always intended to bring on board US venture capitalists. It gives us credibility with US customers," says Mr Montgomery.

Amacis's chief executive is no stranger to the US. He worked on both the east and west coasts in the early 1980s, after graduating from Ulster Polytechnic with a degree in computer science. "It is more difficult to do business in the US, with regional taxes," says Mr Montgomery. "But in business I find no-one knows how to do it initially; it's just a question of finding the next step."

The next step for Amacis is likely to include a flotation on the Nasdaq and rapid growth in the US and Europe. "We are actively looking at continental Europe and the US for acquisitions," says Mr Montgomery. "It's a way of acquiring appropriate skills."

Staffing levels at the company's R&D software centre in Belfast are forecast to more than double by next March, and Amacis is planning to open a German office in the near future.

And the formula behind Tom Montgomery's success? "Many local companies are too inward looking to achieve any degree of international success; you need to be export-focused," he says. "There is a change [in the North] though, with a good undercurrent of companies coming through, just like in Dublin a few years ago."

With the momentum that Amacis has shown in its first two years, few would bet against the arrival of more hi-tech entrepreneurs on the scene in Northern Ireland.