IBM Monday seized on last week's rejection by the ISO of the Microsoft and Ecma International Office Open XML format and said it would throw its development weight behind OpenOffice.org, the most prominent set of open source applications based on the Open Document Format.

IBM, a vocal critic of OOXML standardization, says it will commit 35 veteran programmers to the sparse staff now working on developing the OpenOffice.org specification, which incorporates the ODF.

In addition, IBM has implemented in code its IAccessible2 specification, which makes accessibility features available to the visually impaired, and plans to donate that to the OpenOffice.org effort. The company already has donated the specification itself to the Linux Foundation.

Accessibility features are a critical missing feature within ODF and have delayed the rollout of ODF-compliant applications in Massachusetts, a pioneer in the adoption of open document formats.

IBM also said it will switch to the main OpenOffice.org code base for the text- and other editing applications embedded in Notes 8. Those changes will come with the next maintenance release of the software, which shipped last month. Notes 8 editors now use a derivative of the OpenOffice.org code that IBM developed internally.

IBM officials say the move finally to join wholeheartedly the OpenOffice.org effort is not a coincidence when juxtaposed to the recent ISO rejection of OOXML and the renewed market power standardization would have brought to Microsoft Office.

"The status quo [Microsoft Office] is in direct tension with many customers and governments around the world," says Doug Heintzman, director of strategy for collaboration in the Lotus Software group at IBM. "And you throw in open standards, Web services, [service-oriented architecture] and what is happening with Web 2.0, and you do get one of those perfect-storm situations that potentially changes the world. We are throwing our hat into that ring."

ODF in December earned the ISO standardization that eluded Microsoft's grasp last week. The war of words and rush to influence ISO members participating in the OOXML vote highlight just how contentious the battle for open document formats has become.

IBM's move to throw its weight behind the ODF-based OpenOffice.org is proof that rivals see a chink in the Microsoft Office armor just as many organizations, particularly governments, are evaluating open document formats.

Another example can be seen in Capgemini's announcement that it will offer IT support around Google Apps.

Critics say IBM's jump into OpenOffice.org has been a long time coming and that IBM's simmering feud with Sun, over many software issues starting with Java, has slowed down progress.

The contentiousness has resulted in OpenOffice.org not presenting a unified front against Microsoft, as witnessed by forks in the code propagated by Sun's StarOffice, IBM's unique OpenOffice.org editors and Mac derivatives.

"People realize now they do truly have a common enemy, which is Microsoft or OOXML or the idea that a Microsoft proprietary format could be anointed as an international standard," says Jonathan Eunice, an analyst with Illuminata.