In the latest sniping in the long-running feud over document format standards, IBM this week claimed that Microsoft Corp.'s Excel 2007 corrupted formulas and data in spreadsheets created in the OpenDocument Format.
Microsoft rebuffed the charge, while an industry analyst called the spat an overblown issue that users of ODF-based productivity suites, taking the right steps, can dodge.
Excel 2007 and other parts of Office 2007 began supporting the ODF standard last week with the release of Office 2007 Service Pack 2.
But according to an analysis posted on the personal blog of Rob Weir, chief ODF architect for IBM, Excel 2007 "silently strips out formulas" when reading spreadsheets created by other ODF-compliant programs, such as OpenOffice.org and IBM's Lotus Symphony.
"This can cause subtle and not so subtle errors and data loss," wrote Weir, as results dependent upon dynamic calculations -- today's date, for instance -- become inaccurate.
This data loss is also true when Excel 2007 tries to read spreadsheets created by Microsoft Office 2003 with the aid of a Microsoft-sponsored plug-in or one from Sun Microsystems Inc.
When creating ODF-based spreadsheets, Excel 2007 also saves formulas in a nonstandard location, Weir said. That causes other spreadsheet programs to also fail to read the data properly.
Weir fixed the blame squarely on Microsoft.
"The degree of incompetence needed to explain SP2's poor ODF support boggles the mind and leads me to further uncharitable thoughts," Weir wrote.
Microsoft assigned fault, however, on the latest versions of OpenOffice.org and Symphony that write formulas according to the ODF 1.2 specification. Office 2007's recent update supports ODF 1.1, which is an approved standard. ODF 1.2 has yet to be approved by the nonpartisan OASIS standards body.
When ODF 1.2 is "completed, standardized, and published, we'll be looking at that as the future path for enabling formula interoperability in ODF spreadsheets," wrote Microsoft's senior program manager for Office interoperability, Doug Mahugh, in a blog posted Tuesday. "But we're not there yet."
In his analysis, Mahugh came to the opposite conclusion: Excel 2007 actually rendered results from an OpenOffice.org-created spreadsheet more correctly than Lotus Symphony did.
Microsoft and IBM have been trading barbs on document format standards for half a decade, since Microsoft first announced plans to create an XML-based document format for Office 2007. In reaction, IBM helped engineer the approval of the ODF standard by global standards bodies such as ISO and OASIS in 2006.
That led to Microsoft's successful push to get its document format, now called Office Open XML (OOXML), to also approved by the same standards bodies two years later.
Rather than taking sides in this Rashomon-like squabble, Guy Creese, an analyst with Burton Group, blames the data corruption problems in ODF on the reluctance of standards makers to strictly define the spreadsheet formulas when ODF was first approved.
ODF 1.2 will finally do that, Creese wrote, but in the meantime, others supporting ODF, such as Google Inc. and its Google Docs, had followed OpenOffice.org's de facto example. Perhaps naturally, Microsoft was reluctant to join that camp.
The "takeaway," Creese wrote, is that "ODF interoperability isn't here yet."
However, organizations working with ODF documents can still mostly dodge interoperability problems.
"The best strategy is to stick with one productivity suite as a way to avoid these interoperability problems," wrote Creese. "That way, even if formula support is idiosyncratic, it at least will be consistent within the enterprise."