Sun Microsystems Monday urged a Massachusetts state official to rethink an opinion that Microsoft's Open XML (Extensible Markup Language) meets the state's parameters for an acceptable open document format just because it has been submitted as an open standard.

In a letter signed by Carl Cargill, director of corporate standards for Sun, the company asked the state to keep in mind the reasons for its previous commitment to the Open Document Format for Office Applications (OpenDocument) specification. The office of Massachusetts Governor Mitt Romney has proposed to make OpenDocument the standard format for documents generated by state government agencies.

"The Commonwealth's process began as an effort to ensure that the documents created by its agencies would be owned by those offices and by its citizens for all eternity -- without the need to negotiate or pay for continued access to them again in the future each time a new version of proprietary software is released," Cargill wrote in the letter, viewed Monday by the IDG News Service. "This process began with a desire to create a level playing field so that innovation in the market would flourish, enabling better delivery of government services."

The letter is in response to a statement released by Massachusetts Administration and Finance Secretary Tom Trimarco last Wednesday, two days after Microsoft announced it would submit its proprietary Open XML format to two international standards bodies.

Microsoft will use Open XML in its Office productivity suite. The company submitted it to the International Standards Organization (ISO) and European Computer Manufacturers Association (ECMA) for possible adoption as standards.

Microsoft has committed to handing over its Open XML document formats for Word, Excel and PowerPoint to be adopted as open standards in time for the launch of the next version of its Office software suite, code-named Office 12. In his statement last week, Trimarco said the state is "optimistic that Office Open XML will meet our new standards for acceptable open formats" if Microsoft follows through with this plan.

This leaves the door open for Massachusetts to continue to use Microsoft Office rather than migrate away from the suite, as it would do if it moved to OpenDocument. Microsoft Office does not support OpenDocument, but Sun's StarOffice, IBM's Workplace suite and OpenOffice.org's OpenOffice software do.

OpenDocument is a file format, based on XML and developed within the OASIS (Organization for the Advancement of Structured Information Standards) Web consortium, that covers the features required by text, spreadsheets, charts and graphical documents.

In his letter, Cargill said it would be a "mistake" for Massachusetts to support Open XML based on "a single vendor's promise to submit a new product to a standards body at some point in the future." Instead, the state should move forward with its support of OpenDocument as the standard format for state documents, because not only has it already been approved by a standards body, but it also allows any vendor to build upon the standard, something an ISO or ECMA standard would not allow, he wrote.

"Only after a specification has been approved by a broadly supported standards body -- one that demonstrates acceptable levels of openness by being available to all competing products -- should the Commonwealth consider including that open standard as one of its own," Cargill wrote.

Massachusetts Chief Information Officer (CIO) Peter Quinn finalized a proposal in September that called for state agencies to develop phased plans for migration to OpenDocument beginning Jan. 1, 2007. Since then, there has been some opposition by state officials and citizens to the plan, dissent that has led to a widely publicized debate within both the state senate and the governor's office.

In the meantime, supporters of OpenDocument led by Microsoft rivals Sun and IBM began mobilizing a global effort to push OpenDocument as a global standard format for documents. The companies hosted a meeting at IBM's campus on Nov. 4 -- attended by Quinn as well as representatives from Apple Computer, CA, Intel, Google, Red Hat, Corel, Oracle, Adobe Systems, OpenOffice.org, Nokia and other technology companies -- to formalize those efforts.

Microsoft faces pressure from governments and agencies as they increasingly insist on standards compliance for the software they use. Microsoft executives said the move to submit Open XML to standards bodies would help the company win contracts from public authorities that want software based on open standards.