Alternative APIs, Alepin testified, "were not provided to Lotus and to other companies like Samna [maker of Ami, a GUI-based word processor later bought by Lotus, that was released a year before Word for Windows 1.0]."

The Comes vs. Microsoft trial, which began in early December, is expected to last up to six months. It, along with a lawsuit filed in Mississippi, is among the last remaining antitrust suits filed by states against Microsoft in the late 1990s.

The trial, set in Des Moines, has already seen its share of explosive evidence. In a 2004 e-mail to Microsoft CEO Steve Ballmer and Chairman Bill Gates, then-Windows development chief, James Allchin wrote that Microsoft had "lost sight" of customers' needs and that a Mac if he wasn't working for Microsoft.

Allchin, who retired at the end of 2006 with the launch of Windows Vista, later said that he was "ranting" and being "purposefully dramatic" in his e-mail in order to .

Alepin, who has previously testified against Microsoft in the European Union's antitrust case against the company, is expected to continue testifying this week.