Microsoft has been accused of not maintaining its side of the proposed settlement deal between it and the US Department of Justice (DoJ).

A group of competitors – ProComp (the Project to Promote Competition and Innovation in the Digital Age) – have complained to the DoJ. They claim Microsoft has fallen short of meeting a requirement to make available core software-code that will allow competitors to tune their software to work well with Windows.

Microsoft reached an agreement almost one year ago with the DoJ and later with nine state attorneys general who were also plaintiffs in the antitrust suit. A federal judge is expected to make a decision on the settlement deal any day now. However, Microsoft has already begun implementing some of the required changes.

Microsoft has already agreed to license certain communication protocols that would allow competing developers to build desktop and server software that enjoy the same hooks into Windows as Microsoft products.

"It is our strong conclusion that the information disclosure regime imposed by Microsoft has been a failure to date," ProComp wrote in a letter to the DoJ. The letter of complaint is available for download.

ProComp objects to the licensing terms developers must agree to in order to view the technical information. Microsoft requires licensees to pay fees and sign strict nondisclosure agreements (NDA) before they can even view the protocols.

ProComp believes such terms are onerous and prevent companies from evaluating the effectiveness of the protocols. They also argue that because even the licensing terms are kept secret, the "reasonableness" of those terms cannot be evaluated.

"They must be licensed on terms that make it practical for others to license and redistribute the technology," ProComp said.

Microsoft's legal spokesman Jim Desler disagrees: "Anybody who is interested in or serious about licensing the communication protocols can go through this very straightforward process," he said.

Desler maintains the communication protocols are valuable intellectual property and represent years of research and development. Desler argued that the licensing procedures are adequate and follow industry standard practices.

ProComp's complaint is the second in two months challenging Microsoft's efforts to comply with the deal. In September, the group complained Microsoft did not make Windows XP Service Pack 1 "readily accessible to consumers." This release included a number of features - for example, the ability to launch non-Microsoft Web browsers by default - that Microsoft had been ordered to include under the DoJ's settlement deal.

The DoJ has been meeting with companies that have raised objections to Microsoft's implementation of the settlement, reports claim.