Alex Brown, a document-format expert who is convenor of the process to standardise Office Open XML (OOXML), posted a blog this week reporting the results of tests which he claims reveal that OpenOffice documents do not conform to the International Organization for Standardization's (ISO's) version of the OpenDocument Format (ODF) standard.

Speaking to ZDNet.co.uk this week, Brown, who reported similar problems between Microsoft Office 2007 documents and the OOXML standard, said the standardised version of ODF, known as ISO/IEC 26300:2006, "has a defect which prevents any document claiming validity from being actually valid. Consequently, there are no XML documents in existence which are valid to ISO ODF."

There is a critical flaw in the ODF schema defined by the Organization for the Advancement of Structured Information Standards (Oasis) and approved by ISO as ISO/IEC 26300:2006, according to Brown's blog, which means that no XML document can conform to the standard.

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