The standards body that is pushing Microsoft's Office Open XML document format for approval as an ISO standard published a 2,300-page document on Monday addressing complaints and suggestions about the format made by International Standards Organisation members after it failed to win enough votes in an initial round of balloting.

The most significant changes in the standards submission by Geneva-based Ecma International include the sidelining of a graphics rendering technology used by Microsoft but few other vendors, and the release of more information on how Open XML, the native file format in Office 2007, supports file compatibility with older Office documents.

The compatibility information could help backers of the rival Open Document Format for Office Applications to build better ties between ODF and documents stored in Microsoft's older file formats, said Peter O'Kelly, an analyst at Burton Group in Utah. The current lack of such compatibility is a major weakness for ODF, according to a report that was released Monday and co-written by O'Kelly and fellow Burton analyst Guy Creese.

Ensuring that documents don't lose any formatting or metadata as they are converted from one format to another "is the biggest problem," O'Kelly said. "If you send out a sales presentation and there's a layout change when it comes back, that can be a big deal."

O'Kelly added that he doesn't think Microsoft had deliberately withheld the documentation to thwart the integration efforts of ODF backers. "People working in Microsoft probably found the documentation lacking [as well]," he said.

But Marino Marcich, executive director of the ODF Alliance lobbying group in Washington, contended that having more documentation won't help outside vendors make their file formats more compatible with Microsoft's older ones.

Marcich said via email that a move by Microsoft "to disable access to 'legacy' documents" in newer releases such as Office 2003 Service Pack 3 "effectively cut the legs out from under Microsoft's main selling point for [Open XML], which is 'backwards compatibility.'"

Under ISO rules, the full text of Ecma's document can only be viewed by members of national standards bodies via a password-protected Web portal. But Ecma posted a summary of some the key changes that have been made in the Open XML standards proposal, which is being shepherded by the group's Technical Committee 45.

The length of Ecma's response isn't surprising in light of the fact that ISO members offered up 3,522 written comments about Open XML in the wake of last September's vote on whether to accept Ecma's fast-track standards submission. The proposal received a majority of the votes cast but not the amount required for approval; a second round of voting is scheduled for late next month.

Objections to the Open XML proposal included contentions that Microsoft's file format should be made more interoperable with ODF, which already has been accepted as a standard by Geneva-based ISO. Other objections cited alleged patent violations in Open XML, a variety of specific technical issues and, ironically, the length of the Open XML specification itself. Ecma's original submission to ISO last February was 6,000 pages long; by comparison, the Concise Oxford English Dictionary runs 1,681 pages.

According to the summary of the so-called proposed dispositions document on Ecma's site, many of the group's responses to comments dealt with what observers typically would consider to be esoteric technical changes, such as how Open XML defines colors or page borders in documents, and how it deals with dates in spreadsheets before the year 1900.

But some of the more significant changes to Open XML could be viewed as victories by the anti-Microsoft camp.

For example, another alteration involves downgrading the Vector Markup Language (VML) for generating vector graphics to "deprecated functionality" in favour of using Microsoft's DrawingML technology in all documents. Years ago, VML was rejected as a proposed standard by the World Wide Web consortium, although it was joined together with another specification to create the Scalable Vector Graphics (SVG) standard.

Microsoft continues to use VML in Office and Internet Explorer, but O'Kelly said the software vendor is no longer "pushing VML with a competitive angle, like trying to thwart SVG."

On the other hand, Marcich pointed out that although VML will no longer be part of the main Open XML specification, Microsoft isn't supporting SVG in the document format. "The deck of cards is being shuffled, but at the end of the day, you're dealing with the same tainted deck," he wrote.

Ecma said that among other changes, the Open XML specification will be split into three distinct parts, each based around a corresponding major Office component - Word, Excel and PowerPoint - to make it easier on programmers. In addition, accessibility and non-English language features have been improved, according to Ecma.

It's unclear, though, whether all of the changes will appease regulators at the European Union's competition committee, which today announced a pair of new antitrust investigations of Microsoft that will include looking at whether the company is making Open XML sufficiently open to rival vendors for interoperability.

Ecma didn't mention the idea of merging Open XML into the existing ODF standard in the summary of its response document, nor did it address complaints about possible patent violations. O'Kelly said that merging the two document formats would be "virtually impossible."

In a Monday blog posting, Brian Jones, an Office program manager at Microsoft who is a member of Ecma TC45, praised fellow committee members from Novell and Apple for being "really helpful" in preparing the responses, as well as representatives from BP and the Library of Congress.

Activity already is ramping up in the campaign by Microsoft and Ecma to get Open XML on the same footing as ODF, which already had been accepted as an ISO standard.

In late December, Microsoft said via a company blog posting that compatibility packs enabling users of older versions of Office to read and write documents in Open XML had been downloaded 20 million times. And on Wednesday, Microsoft plans to hold a press briefing about the Open XML ratification effort.

Meanwhile, the report released today by Burton Group argues that Open XML has advantages over ODF and should be adopted by enterprise users, whether or not it is approved as an ISO standard. Burton said that the report wasn't commissioned or paid for by Microsoft, but O'Kelly is scheduled to make a presentation as part of Microsoft's Wednesday press briefing.