Russian programmer Dmitry Sklyarov came to the United States in July to teach a convention crowd about his latest software concoction. Now, Sklyarov is getting a lesson in American jurisprudence.

Use an algorithm, risk going to jail.

Sklyarov, 27, and his employer, ElcomSoft Co Ltd. of Moscow, pleaded innocent Thursday in federal court to charges of creating a software program that lets readers disable certain restrictions imposed by electronic book publishers.

It is the first criminal case prosecuted under the Digital Millennium Copyright Act of 1998. Sklyarov's lawyer, Joseph Burton, says the DMCA is being misapplied by prosecutors in this case.

"If you are a programmer and you work for a company, what are the circumstances under which you can or should be held criminally liable for activity you conduct within the course of your employment?" Burton said. "I think it's a potentially unconstitutional interpretation. I think it's scary."

The young Sklyarov, dressed in a tan suit and open collar shirt, approached the judge and pleaded "not guilty" in thickly accented English, as did ElcomSoft president Alexander Katalov on behalf of his company.

Both Sklyarov and ElcomSoft are charged with five counts of allegedly conspiring for "commercial advantage and private financial gain." The company could be fined $500,000, while Sklyarov faces a $250,000 fine and up to five years in prison on each count.

The programmer remains free on $50,000 bail, but must stay in Northern California.

Sklyarov's algorithm is the basis for a program that allows users to manipulate digitally formatted reading material developed by San Jose-based Adobe Systems Inc.

ElcomSoft's program is legal in Russia and Sklyarov's supporters say his work merely restores the "fair use" privileges consumers have traditionally enjoyed under U.S. copyright law.

Prosecutors said the criminal indictment is the first under the act, which forbids technology that circumvents copyright protections.

Adobe officials complained to the FBI that Sklyarov's employer was selling a program that let users manipulate Adobe's e-book software so the books could be read on more than one computer or transferred to someone else.

The case has generated international protests since Sklyarov was arrested in Las Vegas on July 16. He was preparing to return home to Moscow after speaking at a computer security convention.

Adobe has since dropped its support of the government's case.

The next hearing in the case is set for Tuesday.