A Miami-based vendor that has ported Apple's Leopard operating system to generic PC hardware says Apple's restrictive licensing terms run counter to antitrust laws -- and it's vowing to fight.

Psystar's OpenMac clone is priced at about $399 -- less than one-fifth of what a similar, Apple-branded system sells for. It also represents a direct violation of Apple's end-user license agreement, which forbids third-party installations of Leopard.

But Psystar said Monday that the company believes Apple's terms violate U.S. monopoly laws. "What if Microsoft said you could only install Windows on Dell computers?" said a Psystar employee.

The employee, who would only identify himself as Robert, said Apple grossly overcharges for the hardware on which its operating systems, including Leopard, come preinstalled. "They're charging an 80% markup on hardware," Robert said in a brief phone interview.

He also said Psystar believes Apple's prohibition against third-party installations might not hold up in court: "What if Honda said that, after you buy their car, you could only drive it on the roads they said you could?"

Robert said Psystar will continue to sell the OpenMac system, despite the fact that it appears to violate Apple's EULA. "We're not breaking any laws," he insisted.

OpenMac features Leopard preinstalled atop a 2.2-GHz Intel Core Duo processor with an integrated Intel 950 graphics chip, 2 GB of DDR system memory, and a 250-GB storage drive. It also offers 4 USB ports and a 20x DVD+/-R drive.

The legal questions do not appear to be stopping Mac fans from attempting to check out the clone. Psystar's Web site appeared to have crashed for a time Monday following news coverage of its OpenMac product.